JP6329798B2 - Floating standing tsunami breakwater - Google Patents

Description

  The present invention relates to a levitation standing tsunami breakwater that rises automatically only when a tsunami strikes, and particularly withstands the force of a wave when a large-scale tsunami occurs, and for many years. It relates to a durable breakwater.

  In the past, since experiencing the Great East Japan Earthquake on March 11, 2011, it has been desired to install large-scale tsunami breakwaters along the coastline that can handle large tsunamis. However, installing large-scale tsunami breakwaters along the coastline that can respond to large tsunamis that occur once every several decades or once every several hundred years is an important part of daily life and activities in the fishery industry. It becomes a big obstacle and the scenery is damaged.

  Therefore, it has been desired to install a breakwater that is erected by buoyancy or the like only when a large tsunami strikes without damaging the landscape and without depending on a driving source such as electric power. In this regard, a breakwater has been proposed that includes a breakwater that rotates and stands up around a shaft portion disposed on the levee body (see, for example, Patent Document 1).

JP 2013-36199 A

  By the way, in the breakwater mentioned above, there existed a problem that the intensity | strength and long-term durability of a wave-breaking main body were inadequate, and since the height of a wave-proofing main body was low at the time of standing up, it could not respond to a big tsunami.

  Furthermore, when the blade-shaped rotation assisting member of the wave breaker functions as a stopper for restricting the rotation range of the wave breaker, the blade-shaped rotation assisting member abuts on a locking wall provided on the upper surface of the caisson, Although further rotation of the wave breaker in the clockwise direction is restricted, the blade-like rotation auxiliary member alone cannot support the standing state of the wave breaker against the force of a large wave, and the strength is insufficient There was a problem of being.

  The present invention has been made in view of the above-described conventional problems, and its purpose is to function as a breakwater only when a tsunami strikes, and to be a strong and durable surface that can sufficiently resist the forces of large waves. The purpose is to provide a vertical tsunami breakwater.

  In order to achieve this object, the present invention includes a foundation (2) installed in the ground, and placed on the foundation (2) in a lying state, and when the tsunami occurs, 2) In order to obtain a prestressed concrete structure, the floating type breaker box (3) placed in an upright position on the tip of the floating type breaker box (3) is a tension fixing end (3a). And a cable (continuously disposed between the foundation (2) and the levitated wavebreak box (3) by an external cable system with the bottom of the foundation (2) as a fixed fixing end (2a). 40) and the cable (40) both when the levitated wavebreaker (3) is placed on the foundation (2) in a lying state or when it is placed in an upright state. ) In order to maintain the tension state continuously) Box body Debieta portion of cable deflection provided (3) (D1, D2) and to the comprises a.

  In the present invention, when the levitation type breaker box (3) shifts from the lying state placed on the foundation (2) to the standing state, the levitation type breaker box (3) A concave slope part (14) formed on the upper surface of the foundation (2) and a circular arc part (15) connected to the slope part (14) are further provided as a pivot point.

  In the present invention, when the levitated wave-proof box (3) is placed on the foundation (2) in a lying state, the seawater caused by the tsunami is below the levitated box. And a floating body (30) having a slope (30c) for facilitating the transition from the lying state to the standing state.

  In the present invention, a cable (39) for integration as a prestressed concrete structure is arranged in a tensioned state in the floating type breaker box (3) between adjacent floating type breaker boxes (3). To be.

  According to the present invention, the tension state of the cable is continuously maintained both when the levitated wave breaker is placed on the foundation in a lying state or when it is placed in a standing state. Therefore, the tsunami water pressure acting on the levitation type breaker box when standing up can be fully countered by the prestressing force of the cable, thus standing up against large wave forces and water pressure. A strong and durable levitation-type tsunami breakwater that can sufficiently support the levitation type breakwater box can be realized.

It is sectional drawing which shows the structure of the levitation standing-up type tsunami breakwater which concerns on embodiment of this invention. It is sectional drawing which shows the structure of the footing foundation based on embodiment of this invention. It is sectional drawing which shows the structure of the floating box which concerns on embodiment of this invention. It is sectional drawing which shows the state by which the floating box is mounted in the lying state on the footing foundation which concerns on embodiment of this invention. It is sectional drawing which shows the state by which the floating box is mounted in the standing state on the footing foundation which concerns on embodiment of this invention. It is sectional drawing with which it uses for description at the time of calculating | requiring the thickness (t) of the side wall part of the levitation type | mold breakwater box which concerns on embodiment of this invention. It is sectional drawing which shows the arrangement | positioning state of a deviator in order to maintain the tension | tensile_strength state of a cable in the fall state and standing state of the floating box which concerns on embodiment of this invention.

  Embodiments of the present invention will be described below.

<Structure of the standing tsunami breakwater>
As shown in FIG. 1, when a large wave (BW) arrives due to the tsunami invasion, the levitation standing type tsunami breakwater 1 buoyancy of the levitated wave breaker body 3 against the large wave (BW) with respect to seawater and the hydrodynamic force of the tsunami Due to the (dynamic force due to the flow), the levitated wave breaker 3 placed on the footing foundation 2 in a lying state automatically stands in the direction of the arrow P, and the levitated wave breaker 3 is By functioning as a breakwater, damage caused by ocean waves (BW) is prevented.

  This levitation standing tsunami breakwater 1 is mainly composed of a footing foundation 2 fixed in an embedded state in the ground G, and an arrow P on the footing foundation 2 when large waves (BW) arrive due to the occurrence of a tsunami. It is comprised by the levitating type | mold wave-proof box 3 which transfers to a standing state from a lying state by rotating to a direction.

  The footing foundation 2 is a foundation made of concrete that directly conveys the load of the levitated wavebreaking box 3 placed in a lying or standing state on the ground to the ground G. It is fixed to the ground G in the vicinity area. Therefore, even if this footing foundation 2 is installed on a levee with a height of about 5 m (TP (Tokyo Bay average sea level)), the levitated wave breaker 3 is placed on the footing foundation 2 in a lying state. The coastal landscape will not be damaged in normal times.

  Here, when the length L of the lying state (that is, the height in the standing state) L is set to 10 m (FIG. 3), the levitating type wavebreaking box 3 is placed on the footing foundation 2. When the box 3 is erected, it becomes a breakwater of TP plus 15 m, and it is possible to sufficiently cope with a large tsunami wave (BW) up to a height of about 15 m by the wavebreak surface 3 f which is the front surface. If a higher tsunami is assumed, the height of the embankment should be increased accordingly.

  Further, at a position away from the footing foundation 2 toward the coast in the direction of arrow B by a predetermined distance, the foundation 4 is embedded in the ground G so as to be at the same height as the upper surface 2b of the footing foundation 2. It is fixed. In addition, although the footing foundation 2 and the foundation 4 are provided separately, the footing foundation 2 and the foundation 4 may be fixed to the ground G in an integrated state.

  The footing foundation 2 is formed with a width of about 200 m in the depth direction in the figure perpendicular to the arrow AB direction, and a communication path (not shown) leading to the coast is formed between the adjacent footing foundations 2. Is done. In addition, the upper surface 2b (foundation) of the footing foundation 2 on the side of the arrow A in the direction of the arrow A from the levitation type breaker box 3 at the time of standing up is effectively used by being used as a road during normal times.

  The levitated wave breaker 3 placed in a lying state so as to straddle the footing foundation 2 and the foundation 4 is a box in which a gap portion 21 is formed inside a box-shaped structure. It is formed with a width of about 3 m in the depth direction in the figure orthogonal to each other. Therefore, the levitated wavebreaker 3 is juxtaposed in contact with the upper surface 2b of the footing foundation 2 having a width of 200 m. By the way, there is a problem of water-stopping of the contact parts between the multiple floating breakwater boxes 3, but since the residence time of one wave of the tsunami is within 30 minutes to 1 hour, perfect water-stopping There is no need to think about it.

  In order to integrate these levitation type breakwater boxes 3 into a prestressed concrete structure with the adjacent levitation type breakage boxes 3, the internal cable system is used in the depth direction perpendicular to the arrow AB direction. A cable 39 made of steel is arranged in a tensioned state. In this case, the cables 39 are respectively arranged at one end portion in the arrow B (C) direction and the other end portion in the arrow A (D) direction of the levitation type breaker case 3. The levitation-type wave breaker 3 has a thickness (T) of 1.5 m (FIGS. 1 and 3).

  The levitation-type wave breaker 3 is set to a specific gravity of 0.8 or less by the gap 21. As specific gravity which should be set to this floating type | mold wave-proof box 3, what is necessary is just 0.9 or less, for example. Note that when the levitated wave breaker 3 is placed on the footing foundation 2 in a lying state at one end of the levitated wave breaker 3 in the direction of arrow B (C), In addition, a slope portion 3c is formed for facilitating the inflow of a large wave (BW) due to the tsunami and for facilitating the transition from the lying state to the standing state.

  Further, the buoyancy of a concrete hollow container filled with foamed polystyrene, fiber reinforced plastic, or the like having an inclined surface portion 30c formed so as to be continuous with the inclined surface portion 3c on the extended line of the inclined surface portion 3c of the levitating type wave breaker 3 A body 30 is attached. The slope 30c of the buoyancy body 30 is formed for the same purpose as the slope 3c of the levitation type breaker 3 and the levitation breaker 3 is placed on the footing foundation 2 in a lying state. When placed, it facilitates the inflow of a large wave (BW) to the slope portion 30c of the buoyancy body 30 and facilitates the transition from the lying state to the standing state. The levitation-type wave breaker 3 may be integrally formed with the buoyancy body 30.

  At the other end portion in the arrow A (D) direction in the levitating type wave breaker 3, a notch 22 is formed which is partially opened in the arrow B direction and partially opened in the arrow D direction in the standing state. ing. Since the later-described cable 40 passes through the gap portion 21 and the notch portion 22, the levitation-type wave breaker 3 is inserted into the partition wall D <b> 2 between the gap portion 21 and the notch portion 22 from the outer diameter of the cable 40. A through hole 3d having a slightly larger inner diameter is also formed. In this partition wall portion D2, the through hole 3d through which the cable 40 is inserted is sealed with a predetermined sealing material in order to prevent intrusion of large waves (BW) from the notch portion 22 into the gap portion 21.

  Therefore, in the levitated wave breaker 3, when the levitated wave breaker 3 is placed on the upper surface 2 b of the footing foundation 2, the cable 40 is bent with the partition wall D 2 as a deflection point. That is, the partition wall portion D2 functions as a deviance portion for cable deflection with respect to the cable 40.

  At the other end of the levitated wave-proof body 3, the remaining wall thickness (v) excluding the notch 22 is set to 1.0 m out of the thickness (T) 1.5 m. It is configured so that it can sufficiently withstand the fluid force.

  On the upper surface 2b of the footing foundation 2 facing the notch portion 22 of the levitated wave breaker 3 in the standing state, a notch portion 12 having a substantially cross-sectional triangle shape and partially opened in the direction of arrow C is formed. Yes. The cutout portion 22 of the levitated wavebreaker 3 and the cutout portion 12 of the footing foundation 2 face each other in either the lying state or the standing state, and the cutout portion 22 and the cutout portion 12 allow the cable storage space CS to be opposed to each other. Is formed.

  Between the footing foundation 2 and the levitation type breaker box 3, the fixed side fixing end 2 a provided at the bottom of the footing foundation 2 in the direction of arrow D, and the arrow C of the levitation type breaker box 3. A cable (JIS standard 19S15.2B) 40 made of PC steel by an external cable system is continuously arranged in a tensioned state between the tension fixing end 3a provided at the tip of the direction.

  One end of the cable 40 in the direction of arrow C is embedded in the concrete together with the tension fixing end 3a of the levitated wave breaker 3, and the other end of the cable 40 in the direction of arrow D is concrete with the fixing side fixing end 2a of the footing foundation 2. Embedded in. In addition, the cable 40 is arrange | positioned per 3 m of width | variety of the levitation-type wave-proof body 3 so that the footing foundation 2 and the levitation-type wave-proof body 3 may be straddled (FIG. 6). As a result, the levitated wave breaker 3 has high durability and toughness, and can withstand tsunami water pressure, wave pressure, and the impact force of drifting objects.

  The cable 40 is fixed by an outer cable system in a state where the cable 40 is inserted through the gap 21 and the cable storage space CS (the notch 22 and the notch 12) of the levitated wave breaker 3. When the levitation type breakwater box 3 is placed in a lying state on 2 b, it is bent along the slope 12 c of the notch 12 of the footing foundation 2.

  The intersection D1 between the slope 12c and the bottom surface 12b of the notch 12 in the footing foundation 2 is the intersection D1 when the levitated wave-breaking box 3 is placed on the upper surface 2b of the footing foundation 2 in a lying state. The cable 40 is bent at the deflection point. That is, the intersection point D1 functions as a deviator for deflecting the cable 40. The cable 40 bent at the intersection D1 is in a state along the slope 12c.

<Structure of footing foundation and levitating wavebreak box>
Next, in the levitation standing type tsunami breakwater 1, the levitation type breaker box 3 placed on the upper surface 2b of the footing foundation 2 is shifted to the standing state from the lying state and the levitation type breaker. The structure of the box 3 will be described with reference to FIGS.

  The footing foundation 2 has, in order from the coast side in the direction of arrow B on its upper surface 2b, a concave slope portion 14 formed for positioning when the floating wavebreaker 3 is placed in a lying state, An arcuate portion 15 which becomes a pivotal point when the levitated wavebreaker 3 rises from the arrow Q direction to the arrow P direction and is connected vertically from the end of the slope portion 14 to the levitated wavebreaker. In order to prevent the body 3 from sliding in the direction of arrow A when the body 3 stands up, a convex portion 16 having a vertically upward contact surface 16a that is in contact with the back surface 3b of the levitated wave-proof body 3 is formed. Has been.

  The levitation-type wave breaker 3 is formed with a convex portion 31 having a sloped portion 31 a in contact with the sloped portion 14 of the footing foundation 2 at the other end of the levitation-type wavebreaker 3. Therefore, as shown in FIG. 4, the levitated wave breaker 3 is placed in a lying state in which the inclined surface portion 31 a of the convex portion 31 and the inclined surface portion 14 of the footing foundation 2 are in contact with each other. When the levitation type breaker case 3 stands up in the direction of arrow P due to the fluid force of the tsunami, the bottom surface 3e of the levitation type breaker case 3 comes into contact with the upper surface 2b of the footing foundation and is convex with the rear surface 3b. It is placed in an upright state in which the contact surface 16a of the portion 16 is in contact.

  By the way, as shown in FIG. 6, the levitated wave breaker 3 has a width (W), an overall thickness (T), and a thickness of the side wall portion excluding the gap 21 (t When the specific gravity of the concrete material is 2.5 and the specific gravity of the levitated wavebreaking body 3 is 0.8, the following (Equation 1) and (Equation 1) are developed (Equation 2). ) Holds.

2 (w + T) × t × 2.5 = w × T × 0.8 …………………………………… (Formula 1)
t = (w × T × 0.8) / (2 (w + T) × 2.5) ………………………… (Formula 2)

  When the thickness (t) of the side wall portion excluding the gap portion 21 in the levitated wavebreaking case 3 is obtained based on (Equation 2), it is 0.16 m, that is, 16 cm.

  Subsequently, considering the influence of the hydrodynamic pressure of the tsunami on the length (ie, height) L (10 m) of the levitation-type wave breaker body 3 when standing, the levitation type with the hydrostatic pressure three times as high as the maximum hydrostatic pressure. Design the wave barrier 3. Specifically, the wall thickness v of the base portion of the levitation-type wave breaker 3 with respect to the footing foundation 2 is at least 50 cm. In this case, as shown in FIG. 1, the wall thickness v of the levitation-type wave breaker 3 is set to 1 m.

  The bending moment at the root of the floating wavebreaker 3 at the time of standing is about 1600kN-m per meter when the water level is 10m in height and the hydrostatic pressure is applied. The width of the levitated wavebreaker 3 (W = 3m) Is about 5000 kN-m. In the actual design, a bending moment of about 15000 kN-m, which is three times this, is assumed.

  Since the cable (JIS standard 19S15.2B) 40 has a tensile resistance of 4960 kN according to the standard, considering the safety of 4500 kN as an abnormal tension during a tsunami, the number of cables is 6 and the tensile resistance is 27000 kN. Here, the bending moment that can be resisted by the tensile resistance force (27000 kN) of the six cables 40 is such that the distance between the compressive force and the tensile force of the cross-section of the levitated wave breaker 3 is at least 0.7 m. Assuming that it is about 18000 kN-m or more, which is sufficiently safer than the bending moment of about 15000 kN-m assumed in the design, it is safe in terms of strength. In this case, the levitated wave breaker 3 can maintain a full prestressed state during hydrostatic pressure action even if it receives a water level of 10 m in height when standing.

  In addition, when fixing the cable 40 with respect to the floating type wave-proof body 3 and the footing foundation 2, it introduce | transduces so that effective tension may be set to 20000 kN in anticipation of toughness ensuring and safety. However, since the stress due to the weight of the base portion of the floating wave-proof body 3 in the standing state with respect to the footing foundation 2 is about 0.25 MPa, it can be ignored.

<Tension fixing structure of cable>
By the way, when the cable 40 attached so as to straddle the levitated wave breaker 3 and the footing foundation 2 is placed on the upper surface 2b of the footing foundation 2 in a lying state. The tension fixing state is maintained both in the case of being placed in the standing state. The tension fixing structure of the cable 40 for that purpose will be described below.

  As shown in FIG. 7, assuming that the distance a from the outer edge of the cable 40 to the wave preventing surface 3f of the levitated wave breaker 3 is the cable with the intersection part D1 and the partition wall part D2 functioning as a deviator part in the lying state as deflection points. When 40 is bent, the angle with the horizontal line in the arrow AB direction of the cable 40 arranged in a straight line between the intersection part D1 and the partition wall part D2 is set to 45 degrees, and in the direction of arrow P of the levitated wave-proof box 3 The length of the perpendicular line from the origin org to the rotation center point to the cable 40 is made equal to the distance a.

  The distance b from the upper surface 2b of the intersection part D1 that functions as a devitater part in the footing foundation 2 and the distance b from the bottom surface 3e of the partition wall part D2 that functions as a devitator part in the floating wavebreaker 3 are geometrical. Based on the relationship, it is expressed by the following (Equation 3).

b = a · cot (α) …………………………………………………………………… (Formula 3)

  Here, since the angle α is π / 8, that is, 22.5 degrees, b = 2.414a based on (Equation 3). Therefore, an intersection point D1 that functions as a deviator portion is provided at a position a that is a distance a from the outer edge of the cable 40 to the wave-breaking surface 3f of the floating wave-proofing body 3 and is located at a distance b from the upper surface 2b of the footing foundation 2. If the partition wall portion D2 that functions as a devitater portion is provided at a distance b from the bottom surface 3e of the type wavebreaker 3, the length of the cable 40 is maintained constant in both the lying state and the standing state.

In this way, the levitation-type tsunami breakwater 1 has the levitation-type breakwater box 3 before and after the levitation-type breakage box 3 placed on the upper surface 2b of the footing foundation 2 shifts from the lying state to the standing state. And the arrangement | positioning length of the cable 40 fixed in the tension | tensile_strength state straddling both of the footing foundations 2 can be made constant, Therefore A fixed tension | tensile_strength can be hold | maintained.

<Operation of the standing tsunami breakwater>
The operation of the rising tsunami breakwater 1 having such a configuration will be described. The levitation standing tsunami breakwater 1 has a buoyancy due to the tsunami (BW) reached by the occurrence of the tsunami when the levitation breaker box 3 is placed on the upper surface 2B of the footing foundation 2 in a normal state. Since it flows below the slope portion 30c of the body 30 and the slope portion 3c of the levitated wave breaker 3, the levitation type is caused by the buoyancy of the buoyancy body 30 and the levitating wave breaker 3 and the fluid force of the ocean wave (BW). The wavebreak box 3 easily rotates in the direction of the arrow P from the lying state, and shifts to the standing state.

  At this time, the levitation type breakwater box 3 is in a state in which the inclined surface portion 31 a of the convex portion 31 is in contact with the inclined surface portion 14 of the footing foundation 2, and the bottom surface 3 e is the arcuate portion 15 of the footing foundation 2. 4 (FIG. 4), the arcuate portion 15 rotates around the center of rotation, the bottom surface 3e contacts the top surface 2b of the footing foundation 2, and the back surface 3b contacts the foot. It abuts against the abutment surface 16a of the convex portion 16 of the ting foundation 2.

  As a result, the levitated wave breaker 3 is raised on the upper surface 2b of the footing foundation 2, and the rear surface 3b is brought into contact with the contact surface 16 of the convex portion 16 of the footing foundation 2, so that it slides. The standing state is maintained without any problems.

  At this time, the levitation-type wave breaker 3 is arranged in a tension state in the depth direction perpendicular to the arrow AB direction between the adjacent levitation-type wave breaker 3 and the footing foundation. A plurality of levitated wave breakers 3 placed on the upper surface 2b of 2 are set up almost simultaneously and function as a breakwater against a tsunami.

  The levitation type breaker box 3 of the levitation standing type tsunami breakwater 1 maintains the tension state of the cable 40 continuously arranged so as to straddle the levitation type breaker box 3 and the footing foundation 2 even in the standing state. Therefore, it can sufficiently withstand the tsunami water pressure, wave pressure, and the impact force of drifting objects.

  At the time of subsequent wave pulling, the levitated wave breaker 3 is footed by the prestressing force of the cable 40 fixed to the levitated wave breaker 3 and the footing foundation 2 and the weight of the levitated wave breaker 3. As a result, the upper surface 2b of the foundation 2 is brought into the original lying state, and the normal state of the levitated wave-proof body 3 is restored.

  As described above, in the levitation standing type tsunami breakwater 1, the levitation type breaker box 3 is placed on the upper surface 2 b of the footing foundation 2 in a normal state other than when the tsunami occurs. Because the buoyancy of the levitated wave breaker 3 and the fluid force of the tsunami automatically stand up and function as a high-strength breakwater, the land can be reliably protected from tsunami disasters.

<Other embodiments>
In the above-described embodiment, the case where the footing foundation 2 made of concrete is used has been described. However, the present invention is not limited to this, and the footing foundation 2 made of prestressed concrete is used. A footing foundation 2 having various other structures such as a precast concrete structure may be used.

  In the above-described embodiment, the case has been described in which the levitated wave breaker 3 is placed on the upper surface 2b of the footing foundation 2 in a horizontally lying state, but the present invention is not limited thereto. The tip end side in the direction of arrow B of the levitated wave-breaking box 3 may be placed on the upper surface 2b of the footing foundation 2 in a lying state in which it is slightly inclined upward. In this case, the levitation-type wave breaker 3 can easily stand up when a tsunami wave arrives.

  Furthermore, in the above-described embodiment, the levitated wave breaker 3 is in a standing state perpendicular to the arrow CD direction in which the bottom surface 3e of the levitated wave breaker 3 is in contact with the upper surface 2b of the footing foundation 2. However, the present invention is not limited to this, and the bottom surface 3e of the levitated wave breaker 3 is provided with an inclination so that the levitated wave breaker 3 is in a standing state. You may make it incline slightly to the shore side of the arrow B direction. In this case, the levitation type breaker box 3 is easily restored to the lying state at the time of pulling.

  Furthermore, in the above-described embodiment, the arrangement of the cable 40 has been described with respect to the case where the tension is kept the same in the lying state and the standing state. However, the present invention is not limited to this, and the You may arrange | position the cable 40 so that tension | tensile_strength may increase at the time of standing by changing a position and a shape a little.

  DESCRIPTION OF SYMBOLS 1 ... Levitation standing type tsunami breakwater, 2 ... Footing foundation (foundation), 3 ... Levitation breakage box, 4 ... Foundation, 12, 22 ... Notch part, 14 ... Slope part, 15 ... Arc-shaped part, 16, 31 ... convex part, 21 ... gap part, 30 ... buoyant body, 40 ... cable, D1 ... intersection part (deflection part, deviator part), D2 ... partition part (deflection part, deviator part).

Claims (4)

The foundation installed in the ground,
A floating wave-proof body placed on the foundation in a lying state and placed in a standing state on the foundation when seawater arrives due to the occurrence of a tsunami;
In order to provide a prestressed concrete structure, the foundation and the levitated wave breaker are connected to each other by an external cable system with the tip of the levitated wave breaker as a tension fixing end and the bottom of the foundation as a fixed fixing end. A cable arranged continuously between
In order to continuously maintain the tension state of the cable both when the levitated wavebreaker is placed on the foundation in a lying state or when it is placed in a standing state A levitation rising type tsunami breakwater comprising a foundation and a deviator for deflecting a cable provided on the levitation type breakwater box. When the levitation type breaker box is transitioned from the lying state placed on the foundation to the standing state, a concave shape formed on the upper surface of the foundation as much as possible as a fulcrum of the levitation type breaker box The levitated standing tsunami breakwater according to claim 1, further comprising a slope portion and an arc-shaped portion provided continuously to the slope portion. At the tip of the levitation-type wavebreaking box, when placed in a lying state on the foundation, seawater caused by tsunami easily flows into the lower side of the levitation-type box, and The floating tsunami breakwater according to claim 2, wherein a floating body having a slope portion for facilitating transition from a lying state to the standing state is provided. The cable for integrating as a pre-stressed concrete structure is arrange | positioned in the said floating type | mold breakwater box in the tension | tensile_strength state between adjacent floating type breakwater boxes. The rising tsunami breakwater.

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