JP6364273B2 - Impact force suppression structure - Google Patents

Description

  The present invention relates to an impact force suppressing structure for suppressing an impact force caused by a tsunami.

  When a tsunami arrives, the tip of a wave collides with a coastal building and a large impact force is generated, which may cause the building to be destroyed. For this reason, there is a need for measures to suppress the impact of tsunamis on coastal buildings. For example, in addition to stacking wave-dissipating blocks, there is a case where a structure having a wave-dissipating function for receiving a wave and de-energizing it is installed.

  As an example of the latter, Patent Document 1 describes a wave protection structure composed of a self-supporting pile and a block in which the block is arranged by inserting the upper portion of the self-supporting pile into the hole of the block. Patent Document 2 describes a wave protection structure in which adjacent columnar bodies are closed by walls, and a cushioning material is provided between the columnar bodies and the walls.

  Patent Document 3 discloses a tide wall composed of a set of wall bodies provided with a plurality of openings, and is closed from a state in which the openings communicate with each other by sliding one wall body. State and what can be described. Patent Document 4 discloses a tide facility comprising an energy absorbing face body that is a perforated body installed on the sea side and a water stop face body that is a non-porous body provided on the inland side, and includes an energy absorbing face body and a water stop face body. What is made slidable is described.

JP 2008-38451 A JP 2008-184759 A JP 2011-127387 A JP 2011-1819

  Currently, there is a demand for a structure that can more effectively prevent damage caused by the tsunami and that is simple and advantageous in terms of cost. Moreover, since such a structure usually becomes a part of the regional landscape, it is necessary to devise a landscape.

  In this regard, when wave-dissipating blocks are piled up, there is a risk of becoming a drifting object depending on the wave intrusion form and colliding with the building, and it is not preferable in terms of landscape.

  On the other hand, the wave protection structures of Patent Documents 1 and 2 support a plate-like wave-dissipating body such as a block or a wall with a pile or a columnar body, but the block or the wall itself is subjected to a shock caused by waves. Therefore, there is a concern that the cost is increased in order to secure the supporting force by the pile body and the columnar body. On the landscape side, there is also a sense of pressure due to blocks and walls.

  Patent Document 3 holds a wall body in a slidable manner by a guide frame, and normally allows an opening to communicate with each other to ensure a view, which is preferable in terms of scenery, but it is necessary to switch the position of the wall body during normal times and during flooding. It takes time and is difficult to respond quickly. Further, when the water is immersed, a large water pressure is applied to the wall body to close the opening, and it is necessary to increase the strength to withstand the water pressure. Further, the structure including the guide frame becomes complicated, and there is a concern that the wall body is easily detached from the frame due to damage caused by the impact of waves.

  In Patent Document 4, since the energy absorbing face body is a perforated body, it is possible to reduce the wave. However, compared to this, the rear water stop face that reflects the wave needs to have higher strength, and the wall-like water stop face body. Gives a sense of oppression. In addition, the energy absorbing surface is slidably held by rails, and is usually placed like a shutter in a stack, and is pulled out and placed in a row in the event of an emergency such as a high tide. Is difficult. In addition, a large rail is required, and there is a concern that the energy absorbing face body and the like may be easily detached from the rail due to damage by the impact of the wave as described above.

  An object of the present invention is to provide an impact force suppressing structure that can effectively suppress an impact force caused by a tsunami with a simple structure.

A first invention for solving the above-described problem is a tsunami impact force suppressing structure disposed on the ground on the sea side of an object to be protected, the wave-dissipating body having an opening and an internal space, A holding mechanism for holding a wave body and an auxiliary decelerating body arranged in the internal space , wherein the holding mechanism is a pile body embedded in the ground, and at an upper part of the pile body protruding into the internal space a impact force suppressing structure characterized that you hold the wave dissipating member disposed around the upper portion of the pile body.
A second invention is a tsunami impact force suppression structure disposed on the sea side of an object to be protected, the wave-dissipating body having an opening and an internal space, and a holding mechanism for holding the wave-dissipating body, The auxiliary reducing body disposed in the internal space, and the holding mechanism is a plurality of pile bodies embedded in the ground at a predetermined distance in a direction orthogonal to the wave traveling direction, and protrudes above the ground The wave-dissipating body is held at the upper part of the pile body, and the wave-dissipating body is two perforated plates facing the wave traveling direction, and the two piles adjacent to each other in a direction orthogonal to the wave traveling direction. An impact force suppression structure having both ends of both perforated plates attached to the upper part of the body.
A third invention is a tsunami impact force suppression structure disposed on the sea side of an object to be protected, the wave-dissipating body having an opening and an internal space, and a holding mechanism for holding the wave-dissipating body, And an auxiliary deviating body arranged in the internal space, wherein the wave-dissipating body is a combination of rectangular parallelepiped precast blocks in a cross-beam shape.

  The impact force suppressing structure of the present invention can effectively reduce tsunami by a wave-dissipating body having an opening and an auxiliary de-energizing body, and can prevent generation of a large impact force when it collides with a building. In addition, since the wave-dissipating body has an opening, the supporting force of the holding mechanism is small, and the wave-dissipating body is held with a simple and low-cost structure, and the wave-dissipating block collides with the building as if the wave-dissipating blocks were stacked. There is no risk and there are few restrictions on the site. In addition, there is effect such as opening and is good in scenery.

The holding mechanism of the third invention is a plurality of pile bodies embedded in the ground at a predetermined separation, and it is desirable to hold the wave-dissipating body at the upper part of the pile body protruding to the ground. Moreover, it is desirable that the pile body can relax the force applied to the impact force suppressing structure.
Thereby, a wave-dissipating body can be hold | maintained simply and reliably by a pile body, and it is also possible to relieve the side flow by liquefaction by a pile body. Furthermore, it is possible to make the pile body function like a damper and relieve the force at the time of collision of drifting objects.

In the first invention, the anti Namitai is Ru is arranged around the pile body. The wave-dissipating body is preferably a cylindrical body having an opening.
Thus, by the structure which hold | maintains a cylindrical body with a pile body, the increase in the flow velocity by a contraction flow can be suppressed, and the effective wave suppression is possible. In addition, the appearance is a combination of tubular bodies, which reduces the feeling of pressure like an upright wall, and is preferable in terms of scenery.

A fourth invention is a tsunami impact force suppression structure disposed on the sea side of an object to be protected, the wave-dissipating body having an opening and an internal space, and a holding mechanism for holding the wave-dissipating body, An auxiliary decelerating body disposed in the internal space, and the holding mechanism is a plurality of pile bodies embedded in the ground at a predetermined separation, and the wave-dissipating body at an upper portion of the pile body protruding to the ground The wave-dissipating body is an impact force suppressing structure in which a plurality of arc arches protruding outward are attached to the front of the pile body with a space therebetween .
Also by this, it is possible to effectively reduce the tsunami with a simple structure by the circular arc arch provided with a space therebetween, and the circular arc shape of the circular arc arch reduces the feeling of pressure and is preferable in the landscape.

  The present invention can provide an impact force suppressing structure that can effectively suppress an impact force caused by a tsunami with a simple structure.

The figure which shows arrangement | positioning of the impact force suppression structure 1 The figure which shows the impact-force suppression structure 1 The figure which shows the de-energization of the tsunami by the impact force suppression structure 1 The figure which shows the de-energization of the tsunami by the impact force suppression structure 1 The figure which shows arrangement | positioning etc. of the impact-force control structure 1 The figure which shows cylindrical block 13a etc. The figure which shows the holed hollow body 15a etc. The figure which shows the net-like body 15b The figure which shows the impact-force control structure 1a, 1b, 1c The figure which shows the impact-force control structure 1d and 1e The figure which shows the impact-force control structure 2 The figure which shows the impact-force control structure 3 The figure which shows the impact-force control structure 4

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[First embodiment]
(1. Impact force suppression structure 1)
FIG. 1 is a diagram schematically showing the arrangement of an impact force suppressing structure 1 according to the first embodiment of the present invention. The impact force suppressing structure 1 is disposed on the ground between a seawall 20 on an upright revetment along the coast and a land-side building 30 (protected object). That is, the impact force suppressing structure 1 is disposed on the sea 40 side of the building 30.

  The impact force suppressing structure 1 suppresses the impact force on the building 30 by reducing the wave that travels over the seawall 20 toward the building 30 when a tsunami arrives. The space between the seawall 20, the impact force suppressing structure 1, and the building 30 is normally used as a roadway or a sidewalk. The building 30 is not particularly limited. For example, the building 30 includes a tsunami evacuation building.

  FIG. 2 is a view showing the impact force suppressing structure 1. 2A shows a vertical cross section, and FIG. 2B shows a horizontal cross section. 2A is a cross section taken along line bb in FIG. 2B, and FIG. 2B is a cross section taken along line aa in FIG.

  As shown in FIG. 2, the impact force suppressing structure 1 includes an RC damper pile 11 (holding mechanism), a cylindrical tube 13 (wave absorber), a vertical drain (auxiliary depressing body) 15, a planting 17 and the like. .

  The RC damper pile 11 is a holding mechanism for holding the cylindrical tube 13 and is formed by placing a reinforced concrete pile on the ground. In the present embodiment, a plurality of RC damper piles along a direction orthogonal to the traveling direction of the waves from the sea 40 toward the building 30 (corresponding to the direction from the left side to the right side in FIGS. 2A and 2B). 11 are arranged on a straight line with a predetermined separation. In addition, in this example, although the plane of RC damper pile 11 is a semicircle, not only this but a plane may be circular.

  The upper part of the RC damper pile 11 protrudes on the ground, and the lower part is inserted into an embedding part 101 provided on the ground. The embedding part 101 is a cylinder made of concrete, for example, and is formed so that the vertical cross section of the inner peripheral surface has a substantially arc shape. This arc extends outward as it goes upward, and the inner peripheral surface of the embedded portion 101 has a trumpet shape as a whole.

  The RC damper pile 11 is a pile body that can relieve the impact force by rotation or deformation (mainly bending deformation), and for example, an RC rod-shaped damper described in Japanese Patent No. 4735585 can be used. In addition, a hollow or solid prestressed concrete column in which prestress is introduced in the axial direction can also be used. For example, UFC (ultra high strength fiber reinforced concrete) can be used as the concrete used for the pile. The detailed shape of the inner peripheral surface of the embedded portion 101 described above can be determined in consideration of the final state such as deformation of the RC damper pile 11.

  The cylindrical tube 13 is a wave-dissipating body that receives a wave and decelerates it. For example, a cylindrical tube made of steel is used. The specific gravity of the material is preferably larger than the turbid flow of waves (for example, specific gravity of about 1.5) so that the cylindrical tube 13 does not float out of the turbid flow of waves and escape from the RC damper pile 11. In this case, even if the cylindrical tube 13 is broken, it does not become a drifting material.

  The cylindrical tube 13 is disposed so as to surround the upper portion of the RC damper pile 11 protruding above the ground. The upper end height of the RC damper pile 11 is set so that the cylindrical tube 13 does not come out of the RC damper pile 11 even when a drifting object collides with the upper portion of the cylindrical tube 13 in a state where the water level is raised by the wave. . Alternatively, it is also desirable to fix the cylindrical tube 13 to the ground or the like using an anchor as will be described later.

  The cylindrical tube 13 is provided with an opening 131. In this embodiment, when the side wall of the cylindrical tube 13 is divided into the sea 40 side and the building 30 side, the total area of the opening 131 on the building 30 side is made larger than the total area of the opening 131 on the sea 40 side. .

  A plurality of vertical drains 15 are attached to the internal space of the cylindrical tube 13 as auxiliary depressing bodies for further depressing waves. The vertical drain 15 is, for example, a cylindrical body having a gap, which is cut into an appropriate length and used. Fixing the vertical drain 15 is simplified and it is desirable to allow a certain amount of movement against a wave collision so that the wave shock can be received.

  Planting 17 is applied to the building 30 side behind the cylindrical tube 13. The planting 17 improves the aesthetics and also has a function as an auxiliary depressant. In the present embodiment, greening using the opening 131 is also possible. The cylindrical tube 13 is also a member having a structure advantageous for vegetation and greening.

(2. Tsunami reduction by impact force suppression structure 1)
FIG. 3A is a diagram illustrating a state in which a tsunami has arrived at the impact force suppression structure 1. The wave A ₁ arriving at the impact force suppressing structure 1 collides with the cylindrical tube 13, is reflected in a complicated manner, and a part of the wave A ₁ wraps around the opening 131 as shown by the wave A ₂ and enters the cylindrical tube 13. Thus the wave A ₁ is de-energized.

The wave A ₂ is reflected in a complicated manner on the inner surface of the cylindrical tube 13 or collides with and passes through the vertical drain 15 to further weaken the water force, and becomes a wave A ₃ that leaves the opening 131 and travels toward the building 30. The wave A ₃ is also reduced when passing through the planting 17. Even when the wave passes over the side wall of the cylindrical tube 13 and flows into the cylindrical tube 13, the wave can be similarly reduced in the internal space of the cylindrical tube 13.

In addition, such in the case where a cylindrical pipe 13 without simply provided RC damper pile 11, a strong contraction (jet) occurs due to the wave A ₄ wrapping around between pile as shown in FIG. 3 (b), the building 30 There is a risk that a large impact force may be generated when the vehicle collides with.

In the present embodiment, as shown in FIG. 4 (a), part of the wave A ₁ is directed to the sea 40 side as shown in B ₁ reflected from the cylindrical tube 13. In the present embodiment, to generate a hydraulic jump c by the above wave B ₁ which is opposite direction to the wave A _1, can be de-energized waves A _1. Jumping water is a phenomenon in which the flow of water is disturbed and the flow velocity decreases rapidly, resulting in a normal flow state to a normal flow state.

  In order to generate a water jump for a predetermined tsunami condition to be assumed, the height of the impact force suppressing structure 1 and the shape, size, arrangement, etc. of the opening 131 of the cylindrical tube 13 are appropriately determined for the tsunami condition. Just do it.

  FIG. 4B is a diagram schematically showing conditions for generating the jump water c. That is, when the water level rises due to the tsunami and exceeds the seawall 20, the wave d overflowing the seawall 20 flows into the building 30, and this wave d keeps its momentum and is in a so-called state of impact force suppression. May reach body 1.

In general, the term “shooting flow” means that the Froude number Fr expressed by Fr = u / (g · h) ^1/2 is greater than 1, where u is the velocity of water flow, h is water depth, and g is gravity acceleration. State. A state where the value of the Froude number Fr is smaller than 1 is called normal flow.

Here, the overflow q per unit width from the seawall 20 can be obtained by the following formulas (1) and (2) (Honma's formula: Hydrology official edition edited by the Japan Society of Civil Engineers, revised in 1971) 265).
m = 0.29 + 0.32H / Hd (1)
q = m · H · (2 g · H) ^1/2 (2)
Note that H is the wave height with respect to the upper end of the seawall 20, and Hd is the total height from the water bottom to the upper end of the seawall 20. m is the overflow coefficient.

The wave velocity u and water depth h before the water jump can be approximated by the following formulas (3) and (4) (see Japan Society of Civil Engineers, Hydrological Collection, revised 1971, p.294).
u = (2 g · (Z−h)) ^1/2 (3)
h = q / u (4)
Note that Z is the height of falling water at the seawall 20 and corresponds to the height of waves with respect to the ground surface.

The conditions for the occurrence of a water jump are given by the following equation (5) (refer to P.296, revised edition of 1971, Hydraulic Engineering Collection edited by Japan Society of Civil Engineers).
h ′ / h = ((8u ² / (g · h) +1) ^1/2 −1) / 2 (5)
Here, h ′ indicates the water depth in the normal flow after the jump.

  Accordingly, the height d of the impact force suppressing structure 1 and the shape, size, arrangement, and the like of the opening 131 in the cylindrical tube 13 are such that the water level h ′ is higher than the expected tsunami conditions such as H, Hd, and Z. Anything can be realized. Actual design values can be determined by hydraulic experiments.

Such a jumping water can reduce the tsunami, the impact force on the building 30 as a whole is weakened, and the impact force due to the collision of the jet tsunami does not occur in the building 30. Since the cylindrical tube 13 is permeable to the wave B ₂ reflected from the building 30, the development of overlapping waves between the impact force suppressing structure 1 and the building 30 is suppressed, and the weir on the front side of the building 30 is suppressed. The raised height can be reduced, and the force applied to the building 30 can be reduced. Thus, in the cylindrical tube 13, due to the synergistic effect of the opening 131 and the vertical drain 15 that is the auxiliary de-energizing body, the water level fluctuation (flow velocity fluctuation) due to the water mass at the tip of the tsunami that has passed through the cylindrical pipe 13 becomes mild and sustained A large shock wave force exceeding the wave force can be prevented from being applied to the building 30.

  Furthermore, the impact force suppressing structure 1 according to the present embodiment can capture the drifting object on the front surface, and can prevent the drifting object from directly colliding with the building 30. Alternatively, the impact force can be mitigated even when the drifting object once collides with the impact force suppressing structure 1 and then collides with the building 30. When the drifting object collides with the impact force suppressing structure 1, the impact force can be reduced by the rotation or deformation of the RC damper pile 11. FIG. 4C is a diagram schematically showing this.

  The impact force suppressing structure 1 of the present embodiment described above can effectively reduce the tsunami by the cylindrical tube 13 having a substantially three-dimensional structure having the opening 131 and the auxiliary reducing body, and is large when it collides with the building 30. Generation of impact force can be prevented. In addition, since the cylindrical tube 13 has the opening 131, the support force by the RC damper pile 11 is small, and the cylindrical tube 13 is held in a simple and low-cost structure and becomes a drifting object as if the wave-dissipating blocks are stacked. There is no risk of colliding with 30 and there are few restrictions on the site. In addition to the effect of the opening 131 and the planting 17 and the like, the appearance is a combination of the cylindrical tube 13 having a curved portion, and unlike the upright protective wall that reflects most of the waves, the top end may be low, so a feeling of pressure Is reduced and the landscape is good.

  In the present embodiment, there is an effect of preventing local scouring around the cylindrical tube 13 by reducing the wave as described above. However, even if scouring occurs, the cylindrical tube 13 is held by the RC damper pile 11 and does not lose its function due to slipping out or being largely inclined.

  In addition, auxiliary | assistant decelerating bodies, such as the vertical drain 15, can be easily added and replaced by unitization.

  Moreover, in this embodiment, the RC damper pile 11 has a configuration in which a plurality of RC damper piles 11 are embedded in the ground at predetermined intervals and the cylindrical tube 13 is disposed around the upper portion of the RC damper pile 11 protruding to the ground. The cylindrical tube 13 can be easily and reliably held and can be prevented from becoming a drifting object. Moreover, the increase of the flow velocity by contraction flow does not occur, and the effective wave decrement is possible, and the lateral flow due to liquefaction can be reduced by the RC damper pile 11. The arrangement of the RC damper piles 11 may be determined in order to suitably suppress the lateral flow. Furthermore, the RC damper pile 11 also plays a role as a damper that absorbs force at the time of a collision such as a drifting object.

  Moreover, since a precast member etc. can be used for the cylindrical tube 13 grade | etc., The effort of construction on site is small. Further, the impact force suppressing structure 1 also has a sound insulation effect for reducing noise of a car or the like in a normal state, and is preferable in that an appropriate ventilation property is secured by the opening 131. When the tsunami arrives, it is possible for a person swept away by the tsunami to grab the opening 131 and climb up on the cylindrical tube 13 to evacuate. In addition, by providing illumination or the like inside the cylindrical tube 13 and performing nighttime illumination, the nighttime aesthetics can be further improved by the leaked light from the opening 131 having a design property. Furthermore, the impact force suppressing structure 1 can also have a role as a two wire bank.

  However, the present invention is not limited to that described in the above embodiment. For example, the impact force suppressing structure 1 is not limited to the one provided between the upright revetment and the building 30 as shown in FIG. 1, but is provided between the tide bank 20 on the natural coast and the building 30 as shown in FIG. May be. Alternatively, even where there is no seawall 20, it can be provided on the ground between the sea 40 and the building 30.

  Moreover, in this embodiment, although the RC damper pile 11 and the cylindrical tube 13 are arranged on the straight line, it does not restrict to this. For example, as shown in the impact force suppressing structure 1 ′ in FIG. As the arrangement of the impact force suppressing structure, it may be arranged in an arc shape so as to cover at least a part of the front surface of the building 30. Moreover, you may provide partially the structure which a person and a vehicle can cross.

  Further, as shown in the impact force suppressing structure 1 ″ of FIG. 5C, a buffer material 16 may be disposed between the RC damper pile 11 and the inner surface of the cylindrical tube 13 on the sea 40 side. Thus, it is possible to reduce the force that instantaneously acts on the RC damper pile 11 at the time of collision of waves and drifting objects, or it is possible to provide only a slight gap between the cylindrical tube 13 and the RC damper pile 11, This can also reduce the impact of tsunami and drifting objects.

  Further, the wave-dissipating body for decelerating the wave is not limited to the cylindrical tube 13 described above. For example, instead of the cylindrical tube 13, a concrete cylindrical block 13a as shown in FIG. Similar to the cylindrical tube 13, the cylindrical block 13 a has an opening 131. As concrete, for example, the above-mentioned UFC can be used. In this case, since the specific gravity of the material (concrete) can be about 2.3, it is also preferable in terms of preventing the above-described lifting. The cylindrical tube 13 and the cylindrical block 13a have a circular plane, but the planar shape is not limited to this, and may be a polygonal plane, for example.

  Further, it is also possible to use a UFC design material 13b as shown in FIG. The design material 13b has a plurality of indeterminate openings 131 having different shapes from each other, and can further improve the aesthetic appearance.

  In the present embodiment, as described above, the total area of the opening 131 on the sea 40 side of the cylindrical tube 13 is set smaller and the total area of the opening 131 on the building 30 side is set larger. There is no. By providing the opening 131 on the sea 40 side of the cylindrical tube 13, the wave permeability can be increased. For example, it is possible to make the total area approximately the same on both the sea 40 side and the building 30 side. However, if the total area of the opening 131 on the sea 40 side is made small, there is an advantage that it is easy to ensure the strength so that it will not be damaged at the time of a collision with a drifting object or the like.

  Further, as schematically shown in FIG. 6C, the opening 131 of the cylindrical tube 13 or the like may be determined such that the total area of the lower part is smaller and the total area of the upper part is larger. In addition to these, the shape, size, and arrangement of the opening 131 in the cylindrical tube 13 can be variously determined in consideration of hydraulic effects from the viewpoint of wave deactivation.

  In the present embodiment, the vertical drain 15 is used as the auxiliary de-energizing body. However, the auxiliary de-energizing body for decelerating the wave is not limited to this. Can be determined as appropriate.

  For example, a perforated hollow body 15a as shown in FIG. 7 (a) may be used. The perforated hollow body 15a is obtained by providing a hole 151 on the surface of a hollow sphere. The perforated hollow body 15a can be accommodated inside the frame 152 and disposed in the cylindrical tube 13 as shown in FIG. Further, as shown in FIG. 7C, a die-shaped or polyhedral perforated hollow body 15a 'may be used. In this case, it is also possible to stack them as they are and arrange them in the cylindrical tube 13.

  In addition, as shown in FIG. 8A, a network 15b having a three-dimensional network structure such as Hetimaron (registered trademark) may be used. As the reticulated body 15b, fibers having appropriate flexibility and strength can be used, and the thickness, porosity, wire diameter, and the like can be set to appropriate values from the viewpoint of wave suppression. For example, the porosity can be determined in the range of 80 to 99.99%, the thickness is 0.3 to 100 cm, and the wire diameter is about 0.1 to 5 mm. The arrangement or the like of the mesh body 15b can also be determined as appropriate in order to increase the wave depressing effect. For example, the mesh body 15b can be arranged in the cylindrical tube 13 by being wound or twisted as shown in FIG. . In addition, when using a material having a specific gravity smaller than that of the turbid flow, it is desirable to attach it to the cylindrical tube 13 so that it does not float and dissipate in the waves.

  In addition, as an auxiliary | assistant decelerating body, the laminated body of the punching metal which is hard to rust, or what processed the punching metal as a three-dimensional object can be used. The auxiliary de-energizing body is desirably arranged vertically along the height direction of the cylindrical tube 13 or the like, thereby enhancing the wave de-energizing effect. Furthermore, it is possible to relieve exhaust gas from a vehicle on the road by using an auxiliary de-energizing body having an air cleaning function, or to reduce noise of a vehicle or the like by the auxiliary de-energizing body. Moreover, it is also possible to make it the conditions which are easy to green by planting 17 etc. by moisturizing with an auxiliary | assistant depressor. In addition, when fibers are used for the auxiliary reducer, the fibers that make up the auxiliary reducer are heat resistant, assuming that a tsunami fire will occur, do not burn in the air, and have self-extinguishing properties. It is desirable to select a material that does not generate toxic combustion gas (for example, aramid fiber, glass fiber, etc.).

  In addition, various holding mechanisms can be used for holding the cylindrical tube 13 instead of the RC damper pile 11.

  For example, as shown in the impact force suppressing structure 1a of FIG. 9A, a steel pipe 11a is placed on the ground instead of the RC damper pile 11, and a cylindrical pipe 13 is disposed around the upper part of the steel pipe 11a protruding to the ground. May be. For the steel pipe 11a, it is also possible to place every other steel using the techniques disclosed in, for example, JP 2013-238030, JP 2013-241776, and the like.

  Further, as shown in the impact force suppressing structure 1b of FIG. 9B, a plurality of steel bars 11b may be bundled and used. As the steel bar 11b, for example, the same one as a collision mitigation pole installed on a road can be used. In addition, the steel rod 11b is not limited to a plurality of bundles, and one steel rod 11b having a large diameter may be used.

  Furthermore, as shown to the impact-force control structure 1c of FIG.9 (c), you may use the H-shaped steel 11c. Alternatively, various types of steel can be used instead of the H-shaped steel 11c.

  The cylindrical tube 13 can also be held by these steel pipe 11a, steel bar 11b, and H-shaped steel 11c, and the same effect as described above can be obtained. Further, like the RC damper pile 11 described above, it can also function as a damper that mitigates the collision energy at the time of collision of a drifting object or the like.

  In addition, as shown in the impact force suppressing structure 1d in FIG. 10A, the lower portion of the cylindrical tube 13 is expanded in a flange shape, and the flange portion 132 is simply fixed to the ground by the anchor 19 (holding mechanism). It is also possible.

  Or as shown to the impact-force suppression structure 1e of FIG.10 (b), the lower part of the cylindrical pipe | tube 13 may be extended and embed | buried in the ground, and the opening 131 may be provided only in the part which protrudes on the ground. The cylindrical tube 13 can be easily fixed to the ground by a buried portion 133 (holding mechanism) in the ground.

  Next, second to fourth embodiments of the present invention will be described. Each embodiment will be described with respect to differences from the first embodiment, and the same points will be denoted by the same reference numerals in the drawings and the like, and description thereof will be omitted.

[Second Embodiment]
FIG. 11 is a diagram illustrating the impact force suppressing structure 2 according to the second embodiment. 11A is a vertical cross section of the impact force suppressing structure 2, and FIG. 11B is a view illustrating the upper surface of the impact force suppressing structure 2. FIG. FIG. 11A shows a cross section taken along line ee of FIG.

  The impact force suppression structure 2 includes an RC damper pile 11 (holding mechanism), planting 17, a plurality of arc arches 21 (wave absorbers), a net-like body (auxiliary depressing body) 23, and the like.

  As in the first embodiment, the RC damper pile 11 is provided on the ground and is orthogonal to the wave traveling direction (corresponding to the direction from the left side to the right side in FIGS. 11A and 11B). A plurality of lines are arranged on a straight line at predetermined intervals along the direction of the line. In this embodiment, the RC damper piles 11 adjacent to each other are connected to each other by the connecting portion 25, and the rigidity as a whole is increased. One end of the arc arch 21 is attached to the upper part of the RC damper pile 11 protruding to the ground, and this is held.

  The arc arch 21 is a narrow arch-shaped member provided so as to protrude outward, and is formed of steel, concrete, or the like. In the case of using concrete, it is possible to reduce the member thickness by using, for example, the above-mentioned UFC. A plurality of arc arches 21 are provided at intervals, and one end of each arc arch 21 is attached to the connecting portion 21 a at the upper part of the corresponding RC damper pile 11. The other end of the arc arch 21 is fixed to the fixed plate 21b.

  The connecting portion 21a attaches the arc arch 21 to the RC damper pile 11 so as to be able to advance and retreat along the wave traveling direction, and a known mechanism such as a sliding buffer mechanism can be applied. By this connecting portion 21a, it is possible to mitigate the impact that is instantaneously applied to the arc arch 21 at the time of the collision of drifting objects or waves.

  The fixed plate 21b is formed on the ground surface with concrete or the like. In addition to fixing the arc arch 21, the fixing plate 21 b also has a role as a scouring prevention body that prevents scouring by waves.

  In the present embodiment, a plurality of arc arches 21 are thus provided in front of the RC damper pile 11, and slit-like openings 24 are formed between adjacent arc arches 21. Although the arc arch 21 is difficult to realize the wave-dissipating function by itself, a plurality of the arc-shaped arches 21 arranged side by side with the opening 24 as described above constitute a wave-dissipating body that receives waves and decelerates them.

  In the inner space covered by the arc arch 21, a mesh member 23 is attached so as to block the opening 24 as an auxiliary depressor for further depressing the wave. The mesh body 23 is the same as the mesh body 15b.

  A similar mesh body 23 is also attached to the building 30 side behind the RC damper pile 11 and functions as an auxiliary deenergizing body that decelerates waves that have passed through the RC damper pile 11. Similarly to the above, the thickness, porosity, wire diameter, and the like of each mesh body 23 can be appropriately determined from the viewpoint of wave deactivation.

  A planting 17 is provided outside the arc arch 21 so as to cover the opening 24. The planting 17 has a function as an auxiliary decelerating body that decelerates waves in addition to the effect on the landscape. It is also possible to use the planting 17 instead of the mesh body 23 behind the RC damper pile 11.

  This impact force suppression structure 2 can also achieve the same effects as those of the first embodiment, effectively reduce tsunami with a simple structure, and can suppress the impact force on the building 30. Further, the arc shape of the arc arch 21 reduces the feeling of pressure and is excellent in terms of scenery.

[Third embodiment]
FIG. 12A is a diagram showing the impact force suppressing structure 3 according to the third embodiment, and shows the front as viewed from the sea 40 side. FIG. 12B is a view showing the upper surface of the impact force suppressing structure 3. The traveling direction of the wave corresponds to the direction from the bottom to the top of FIG.

  As shown in the figure, the impact force suppressing structure 3 is configured by arranging a plurality of two perforated plates 31 (wave absorbers) between adjacent pile bodies 34 (holding mechanisms). The two perforated plates 31 are arranged facing the wave traveling direction.

  The pile body 34 is for holding the perforated plate 31 to prevent movement. A plurality of pile bodies 34 are provided on the ground, and are arranged on a straight line at a predetermined distance along a direction orthogonal to the wave traveling direction (corresponding to the horizontal direction in FIGS. 12A and 12B). Be placed. As the pile body 34, for example, a PHC (Pretensioned Spun High Strength Concrete Piles) pile or the like can be used.

  The perforated plate 31 is a wave-dissipating body for receiving a wave and de-energizing it, and is a plate material provided with a plurality of openings 311. The two perforated plates 31 are provided along a direction orthogonal to the wave traveling direction, and cylindrical sockets 32 are provided on both sides thereof. The perforated plate 31 is arranged with a socket 32 placed around the upper portion of the pile body 34 protruding to the ground. Between the perforated plates 31, for example, an auxiliary reducing body 35 such as the above-described net-like body is disposed.

  The impact force suppressing structure 3 can also achieve the same effect as that of the first embodiment, effectively reduce the tsunami with a simple structure, and suppress the impact force on the building 30. In addition, the above-described impact force suppressing structures 3 can be arranged in a plurality of rows in the front-rear direction along the wave traveling direction. Moreover, the perforated plate 31 is good also as a folding half shape (wave shape).

Further, in the impact force suppressing structure 3, as shown in FIG. 12C, a flap gate (opening / closing body) 33 that can be opened only on the sea 40 side may be provided below the perforated plate 31. Accordingly, the flap gate 33 is opened by the pressure of the wave B ₂ reflected from the building 30 (see FIG. 4A), and the wave B ₂ is passed to the sea 40 side, whereby the wave A ₁ (FIG. 4A). It is also possible to further depressurize (see). Such an opening / closing body is also applicable to other embodiments.

[Fourth Embodiment]
FIG. 13 is a diagram showing an impact force suppressing structure 4 according to the fourth embodiment. 13A is a front view of the impact force suppressing structure 4 viewed from the sea 40 side, FIG. 13B is an upper surface of the impact force suppressing structure 4, and FIG. 13C is a line f in FIG. The cross section by -f is shown. The traveling direction of the wave corresponds to the direction from the bottom to the top of FIG.

  As shown in the figure, the impact force suppressing structure 4 includes a plurality of precast blocks 41 (wave-dissipating bodies), steel pipe piles 43 (holding mechanisms), etc., and is substantially the same as the PBS (pile-driving connection block) method. It was built.

  The steel pipe piles 43 are provided by being driven in four directions on the ground at predetermined intervals, and the upper portions of the respective steel pipe piles 43 project to the ground. The steel pipe pile 43 is for holding the precast block 41 and preventing movement.

  The precast block 41 has a narrow rectangular parallelepiped shape that is long in one direction, and holes are formed at both ends in the longitudinal direction. In the present embodiment, the upper portions of the steel pipe piles 43 are respectively passed through these holes, and a plurality of precast blocks 41 are combined and arranged in a cross beam shape. Thereby, an opening 42 is formed between the upper and lower precast blocks 41. In the internal space of the cross-shaped precast block 41, for example, the auxiliary reducer 44 such as the vertical drain described above is disposed. Although it is difficult for the precast block 41 to realize a wave-dissipating function by itself, a wave-dissipating body that receives a wave and decelerates it by combining a plurality of precast blocks 41 with an opening 42 as described above. Configure.

  This impact force suppressing structure 4 can also achieve the same effect as that of the first embodiment, effectively reduce the tsunami with a simple structure, and suppress the impact force on the building 30.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

1, 1 ′, 1 ″, 1a to 1e, 2, 3, 4; impact force suppression structure 11; RC damper pile 11a; steel pipe 11b; steel bar 11c; H-shaped steel 13; cylindrical pipe 13a; Design material 15; vertical drains 15a and 15a '; perforated hollow bodies 15b and 23; mesh body 16; cushioning material 17; planting 19; anchor 20; seawall 21; arc arch 21a; 24, 42, 131, 311; opening 30; building 31; perforated plate 32; socket 33; flap gate 34; pile bodies 35 and 44; auxiliary depressor 40; sea 41; Insertion part 132; Flange part 133; Buried part

Claims (6)

A tsunami impact force suppression structure that is placed on the sea side of the protected object,
A wave absorber having an opening and an internal space;
A holding mechanism for holding the wave-dissipating body;
An auxiliary neutralizer disposed in the internal space;
Equipped with a,
The holding mechanism is a pile body buried in the ground, at the top of the pile body which projects into the interior space, and characterized that you hold the wave dissipating member disposed around the upper portion of the pile body Impact force suppression structure. A tsunami impact force suppression structure that is placed on the sea side of the protected object,
A wave absorber having an opening and an internal space;
A holding mechanism for holding the wave-dissipating body;
An auxiliary neutralizer disposed in the internal space;
Equipped with a,
The holding mechanism is a plurality of pile bodies embedded in the ground at a predetermined interval in a direction orthogonal to the wave traveling direction, and holds the wave-dissipating body at the upper part of the pile body protruding above the ground,
The wave-dissipating body is two perforated plates facing the wave traveling direction, and both ends of the two perforated plates are respectively disposed on top of the two pile bodies adjacent to each other in a direction perpendicular to the wave traveling direction. An impact force suppressing structure characterized by being attached . A tsunami impact force suppression structure that is placed on the sea side of the protected object,
A wave absorber having an opening and an internal space;
A holding mechanism for holding the wave-dissipating body;
An auxiliary neutralizer disposed in the internal space;
Equipped with a,
The anti Namitai is impact force suppressing structure, characterized in der Rukoto a combination of precast blocks of rectangular parallelepiped in a grid shape. 4. The impact force according to claim 3 , wherein the holding mechanism is a plurality of pile bodies embedded in the ground at a predetermined distance, and holds the wave-dissipating body at an upper portion of the pile body protruding on the ground. Suppression structure. The impact force suppression structure according to any one of claims 1, 2, and 4 , wherein the pile body can relieve a force applied to the impact force suppression structure. A tsunami impact force suppression structure that is placed on the sea side of the protected object,
A wave absorber having an opening and an internal space;
A holding mechanism for holding the wave-dissipating body;
An auxiliary neutralizer disposed in the internal space;
Equipped with a,
The holding mechanism is a plurality of pile bodies embedded in the ground at a predetermined separation, and holds the wave-dissipating body at the upper part of the pile body protruding on the ground,
The anti Namitai is impact force suppressing structure for a plurality of arc arches which is convex outward, the Der Rukoto those attached to the front of the pile body at intervals, wherein.