JP2010275850A - Permeable type bank body structure, and permeable sea area control structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permeable type bank body structure, and a permeable marine area control structure, capable of narrowing a space between bank bodies, without requiring structure of each bank body to be enlarged, when widening a space between foundation piles to reduce an interference between the foundation piles of the bank body. <P>SOLUTION: This permeable type bank body structure 10 includes the permeable type bank bodies 11 provided with a wall part and a horizontal part having an opening and for exhibiting breakwater performance, and a foundation structure 12 constituted of the foundation piles 29a, 29b driven from a water bottom into a soil, in order to support the bank bodies, each bank body 11 includes overhung structures 41, 42 projected toward a side face outer side with respect to a horizontal position of the foundation pile, and an area of the horizontal part is reduced in the overhung structure. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a transmission type bank structure and a transmission type sea area control structure composed of a transmission type bank having a wave-dissipating performance.

In order to ensure the tranquility of the harbor, it is effective to construct an impermeable breakwater on the offshore side (to prevent transmitted waves to the land side), but to prevent coastal erosion such as sandy beaches, Impervious breakwaters are not suitable. Whether or not coastal erosion occurs is mainly determined by the characteristics of sand (specific gravity and shape) and constant wave characteristics. Therefore, it is considered that the influence of erosion due to waves (storms) that strike once every several years to several decades is small in the long term. When a breakwater is built at a point where coastal erosion prevails, the reflectance on the front of the breakwater increases and sand on the offshore side of the installation point is eroded, while sand accumulates on the land side. For this reason, countermeasures for front surface erosion and back surface deposition are newly required.
Compared to such impervious type breakwaters, in order to prevent coastal erosion, a transmission structure with wave-dissipating performance by reducing both the transmittance and reflectivity around the target point is always effective against waves. It has been known. For example, as shown in FIG. 11, when a transmissive structure A is constructed and an incident wave arrives at the transmissive structure A from the offshore side, the reflected wave and transmitted wave generated by the incident wave are transmitted in the transmissive structure A. By reducing both, frontal erosion and backside deposition can be reduced.

  Examples of the transmission structure described above include a pile-type wave breaking structure such as Patent Document 1 and a transmission type sea area control structure such as Patent Documents 2 and 3. As shown in the front view of FIG. 12, the latter transmission-type sea area control structure 1 has a box-shaped dam body 2 installed on a foundation pile 3 with a gap 5 between the bottom of the foundation pile 3 and the dam body 2 is vertical. It consists of a front wall consisting of a wall 6 and an inclined wall 7, an intermediate wall, a rear wall, a side wall 8, a bottom plate and a top plate, and a vertical slit 6 and an inclined wall 7, an intermediate wall and a rear wall are provided with transmission slits 9, Openings are formed in the bottom plate and the top plate.

Japanese Patent Laid-Open No. 02-24408 JP 2007-262890 A JP 2008-14136 A

  Since the transmission type structure is hollow, the stability cannot be maintained by a weight type such as a normal breakwater. For this reason, the foundation pile 3 is driven and fixed as shown in FIG. Here, as shown in FIG. 13, when the transmissive structure is constructed by arranging the levee bodies B1 and B2 (for example, the dam body 2 of FIG. 12), the interval W1 between the dam bodies B1 and B2 is as shown in FIG. Narrower is preferable for reducing the transmittance of the transmitted wave, but if so, the interval W2 between the foundation pile C1 of the dam body B1 and the foundation pile C2 of the dam body B2 also becomes narrow. If the distance W2 between the foundation piles C1 and C2 driven from the bottom T into the ground G is narrow, the following problems (1) and (2) occur due to interference between the piles. That is, (1) the pile support force is lower than in the case of a single pile due to interference between the piles. For this reason, in order to ensure a required supporting force, it is necessary to widen the space | interval W2 of a pile or to lengthen the penetration depth of a pile. Longer piles will result in poor economic and workability. (2) The scouring amount of the ground G around the piles is increased due to the interference between the piles, and the stability of the piles is lowered due to the large scouring around the piles.

  In order to increase the interval W2 between the piles, the interval W1 between the dam bodies in FIG. 13 must be increased. However, if the interval W1 between the levee bodies is increased, the waves are easily transmitted to the back side as described above. The transmittance will increase. In order to avoid such an increase in transmittance, it is necessary to increase the structure of the bank body itself (increase the lateral width of the bank bodies B1 and B2 in FIG. 13) to ensure the transmission performance per construction extension including the interval. There is.

  On the other hand, when the horizontal position of the foundation piles C1, C2 is changed to the inside of the levee to increase the interval W2 between the piles and the interval W1 between the levee bodies is reduced, the levee body is positioned relative to the horizontal position of the foundation piles C1, C2. The outer portion has an overhang structure, and the force applied to the overhang structure portion of the bottom plate is increased due to the effect of lifting pressure, which may cause the member to be destroyed.

  In the present invention, when the interval between the foundation piles is widened in order to reduce the interference between the foundation piles of each levee body, it is not necessary to increase the structure of the levee body, and the interval between the levee bodies is reduced. An object of the present invention is to provide a transmission type levee body structure and a transmission type sea area control structure that can be used.

  A transmission type levee structure for achieving the above object is provided with a transmission type dam body having a wall portion having an opening and a horizontal portion and exhibiting wave-dissipating performance, and from the bottom of the water to support the dam body. A base structure composed of a foundation pile driven into the ground, and a transmission-type dam body structure, wherein the dam body has an overhanging structure protruding outward from the side surface with respect to the horizontal position of the foundation pile, The area of the horizontal portion in the projecting structure is reduced.

  According to this transmission type levee structure, the levee body can be arranged so that the side end portions of the dam bodies approach each other by providing the projecting structure in which the dam body protrudes to the outer side of the horizontal position of the foundation pile. As a result, the distance between the dams is reduced and the distance between the foundation piles is increased. Since the interval between the levee bodies becomes narrow, the transmittance does not increase, so that the dam body width per box does not increase and the structure of the dam body does not increase. Moreover, since the space | interval of foundation piles becomes wide, interference between foundation piles can be reduced and the amount of scouring around a foundation pile can be decreased. Further, by reducing the area of the horizontal portion in the overhang structure, the lifting pressure applied to the horizontal portion can be released and reduced, so that the risk of member destruction in the overhang structure portion can be eliminated.

  In the transmission type levee structure, the horizontal portion has a bottom plate and a top plate, and an opening is provided in each of the bottom plate and the top plate in the overhang structure, thereby reducing an area of the horizontal portion in the overhang structure. Thus, the lifting pressure can be reduced.

  Moreover, it is preferable that the wall part of the bank body has a front wall and a slope wall on the front side, and that each of the front wall and the slope wall in the projecting structure is provided with complementary openings. When the levee bodies are arranged side by side, the openings of complementary shapes of the front wall and the slope wall in the overhang structure can be integrated to form a new opening, which can contribute to the improvement of the wave-dissipating performance.

  A transmission type sea area control structure for achieving the above object is configured by arranging at least two of the above-mentioned transmission type levee structures, and the sides of the at least two transmission type dam structures are opposed to each other. And when it arrange | positions so that it may approach, the foundation piles of each said transmission type levee body structure are spaced apart and located in the horizontal direction by the said overhang | projection structure, It is characterized by the above-mentioned.

  According to this transmission type sea area control structure, since the bank body of the above-mentioned transmission type bank structure is provided with an overhanging structure that protrudes to the outside of the side surface with respect to the horizontal position of the foundation pile, the side surfaces of each bank body face each other. When it arrange | positions so that it may approach, while the space | interval between embankments becomes narrow, foundation piles are spaced apart in the horizontal direction and the space | interval of foundation piles becomes wide. Moreover, the transmittance | permeability does not become large because the space | interval between embankments becomes narrow. Moreover, since the space | interval of foundation piles becomes wide, interference between foundation piles can be reduced and the amount of scouring around a foundation pile can be decreased. Furthermore, since the lifting area applied to the horizontal part can be reduced by reducing the area of the horizontal part in the overhang structure of each levee body, each levee in the permeable sea area control structure composed of at least two permeable type dam body structures. It is possible to eliminate the possibility of member destruction in the overhanging structure portion of the body.

  In another transmission type sea area control structure, the wall portion of the levee body has a front wall and a slope wall on the front side, and openings of complementary shapes on the front wall and the slope wall in the overhang structure, respectively. At least two of the above-mentioned transmission type levee structures provided side by side, and when each dam body of the at least two transmission type dam structures is disposed so that the side faces face each other and approach each other, The foundation piles of the type levee body structure are positioned apart from each other in the horizontal direction by the overhang structure, and the openings of the complementary shapes of the front wall and the slope wall in the overhang structure are integrated into a new An opening is formed.

  According to this transmission type sea area control structure, the distance between the dike bodies is narrowed and the distance between the foundation piles is widened, and the openings of the complementary shapes of the front wall and the slope wall in the overhang structure are integrated. By constructing a new opening, it is possible to contribute to the improvement of the wave-dissipating performance.

  Moreover, the division block for the bank body is divided into a plurality of blocks so that the bank body of the transmission type bank body structure is separated in the vertical direction. By constructing the levee body from a plurality of divided blocks, it is possible to construct a transmission type dam body structure relatively easily by sequentially inserting each divided block into a foundation pile driven into the bottom of the water and stacking them.

  According to the transmission type levee structure and the transmission type sea area control structure of the present invention, since the interval between the foundation piles can be widened, interference between the foundation piles of each dam body can be reduced, and the scouring amount around the foundation piles Can be reduced. For this reason, the fall of the supporting force by a foundation pile can be prevented. Further, since the interval between the bank bodies can be narrowed, the bank body width per box is not increased, the structure of the bank body is not increased, and the transmittance is not increased.

The top view (a) which shows the transmission type levee body structure by this Embodiment, the side view (b) seen from the b direction of Fig.1 (a), the front view (c) similarly seen from the c direction, and d It is a rear view (d) seen from the direction. It is the perspective view (a) of the transmission type levee body structure of FIG. 1, and the perspective view (b) seen from another angle. It is sectional drawing which cut | disconnected the transmission type bank body structure of Fig.1 (a) in the III-III line direction. It is sectional drawing similar to FIG. 3 for demonstrating the flow of the normal water in the transmission type levee body structure of this embodiment. It is sectional drawing similar to FIG. 3 for demonstrating the force and flow of water which are added at the time of a storm in the transmission type levee body structure of this embodiment. FIG. 4 is a front view of a transmission type sea area control structure in which two transmission type bank structures 10 of FIGS. 1 to 3 are arranged side by side. It is a front view of the permeation type sea area control structure constituted by arranging two conventional permeation type bank structures. It is a figure which shows the outline | summary of the experimental apparatus used for the two-dimensional moving bed experiment of this experiment example. It is a graph which shows the result of having measured the average scouring depth and the maximum scouring depth about the experiment example and the comparative example. It is a graph which shows the result of having measured the average scouring depth and the maximum scouring depth about the experiment example and comparative example which changed wave conditions. It is the schematic for demonstrating the reflected wave and transmitted wave which arise with an incident wave when an incident wave arrives at the constructed transmission structure. It is a front view of the permeation | transmission type | mold sea area control structure disclosed by patent document 2. FIG. It is a schematic front view for demonstrating a problem when installing two conventional bank bodies side by side. It is sectional drawing similar to FIG. 3 which shows the modification of this embodiment. It is sectional drawing similar to FIG. 3 which shows another modification of this embodiment. It is sectional drawing similar to FIG. 3 which shows another modification of this embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a plan view (a) showing a transmission type dam structure according to the present embodiment, a side view (b) seen from the direction b of FIG. 1 (a), a front view (c) also seen from the direction c, and It is the rear view (d) similarly seen from d direction. FIG. 2 is a perspective view (a) of the transmission-type dam structure of FIG. 1 and a perspective view (b) seen from another angle. FIG. 3 is a cross-sectional view of the transmission type dam structure of FIG. 1A cut along the line III-III.

  As shown in FIGS. 1 (a) to 1 (d), 2 (a), 2 (b), and 3, a transmission type dam body structure 10 includes a transmission type dam body 11 having wave-dissipating performance, and a dam body. 11 and a foundation structure 12 including a plurality of foundation piles 29a, 29b, 29c, and 29d. The foundation piles 29a and 29b are arranged on the front side (offshore side), and the foundation piles 29c and 29d are arranged on the rear side (land side).

  The dam body 11 has a front wall 13 extending in the vertical direction on the front side (offshore side) and a slope wall 14 inclined from the upper end of the front wall 13 and extends in the vertical direction on the rear side (land side). It has a rear wall 15, an intermediate wall 16 parallel to the front wall 13 between the front surface and the rear surface, and side walls 17 and 18 on both side surfaces. Moreover, the bank body 11 has a top plate 19 at the top in the horizontal direction and a bottom plate 20 at the bottom in the horizontal direction.

  The front wall 13 is provided with a front slit 21 extending in the lateral direction and opened in the middle of the wall surface, and the slope wall 14 is provided with a slope slit 22 extending in the lateral direction and opened in the middle of the slope. The rear wall 15 is provided with a plurality of rear slits 23 in the vertical direction as shown in FIG. As shown in FIG. 3, the intermediate wall 16 is provided with a plurality of intermediate slits 24 in the vertical direction. Further, the top plate 19 is provided with a top plate opening 25, and the bottom plate 20 is provided with a plurality of bottom plate openings 26. Moreover, although the opening is not provided in the side walls 17 and 18, you may provide.

  In addition, a wall portion 16 a is provided on the intermediate wall 16 at a position substantially the same as the slope slit 22 of the slope wall 14. A rear slit 23 is also provided on the upper portion of the rear wall 15.

  In addition, in the bank body 11, the preferable opening ratio (ratio of the opening area to the wall area) of each opening is 15 to 25% for the front slit 21 + slope slit 22, 20 to 30% for the intermediate slit 24, and 30 for the rear slit 23. ~ 40%. When openings are provided in the side walls 17 and 18, the opening ratio is preferably 5 to 15%. Further, the opening ratio of the top plate opening 25 is preferably 25 to 35%, and the opening ratio of the bottom plate opening 26 is preferably 25 to 35%.

  As shown in FIGS. 1 (a), (c), (d), and FIGS. 2 (a) and 2 (b), the dam body 11 has projecting structures 41 and 42 projecting to the outside of the side walls 17 and 18, and The transmission type levee structure is constructed. The protruding structures 41 and 42 are provided with protruding portions 43a, 43b, and 43c in the vertical direction on the front surface side, so that openings 43 and 44 having complementary shapes are formed in the front wall 13 and the slope wall 14, When the two levee bodies 11 are arranged, the two openings 43 are integrated with each other, and the two openings 44 are integrated with each other to form new opening slits 51 and 52 (FIG. 6). It has become.

  Further, as shown in FIGS. 2A and 2B, the protruding structures 41 and 42 are provided with a plurality of intermediate protrusions 46 in the vertical direction in the middle of the depth direction, and a plurality of rear protrusions in the vertical direction on the rear surface side. A portion 47 is provided. When the two levee bodies 11 are arranged, the openings formed by the intermediate protrusions 46 are integrated to form a new opening, and the openings formed by the protrusions 47 on the rear surface are integrated. Thus, a new opening is formed.

  Further, in the protruding structures 41 and 42, the protruding portions 43a, 46, and 47 are located on the bottom plate of the horizontal portion, and relatively large openings 45 and 45 (FIG. 2) are provided between the protruding portions 43a, 46, and 47. Further, the protrusions 43c and 47 are located on the top plate of the horizontal portion, and a relatively large opening 48 is provided between the protrusions 43c and 47, so that the areas of the bottom plate and the top plate are small. It has become. For this reason, even if the lifting pressure increases, the lifting pressure escapes through the openings 45 and 48, so that the force applied to the bottom and top plates of the horizontal portions in the overhang structures 41 and 42 is reduced.

  As described above, the offshore foundation piles 29a and 29b are provided in the lateral direction of FIGS. The horizontal position is relatively displaced inward, and the land-side foundation piles 29c and 29d are in a positional relationship in which the horizontal position in the horizontal direction in FIG. .

  Moreover, the whole bank body 11 is comprised from the some division blocks 31, 32, 33 made from concrete like FIG.1 (b)-(d). The plurality of divided blocks 31, 32, and 33 are relatively thin by being divided in the horizontal direction so as to be separated in the vertical direction.

  Construction of the transmission type dam body structure 10 can be performed as follows. First, foundation piles 29a to 29d are driven and constructed from the bottom T into the ground G, and then the divided blocks 31, 32, and 33 are sequentially formed in the through holes 30 of the divided blocks 31 to 33 (FIG. 1 (c). ) Insert from (d)) into foundation piles 29a-29d and stack. Thereby, the transmission type dam body structure 10 can be constructed more simply than the case where the dam body 11 is integrally formed without being divided. A stopper (not shown) for locking the lowermost divided block 31 at a predetermined height position is provided on the outer periphery of the foundation piles 29a to 29d.

  The gap H1 (FIG. 3) from the lower end of the bottom slab 20 (the lower end of the block 31) to the bottom T of the dam body 11 is set to a value within a predetermined range as follows, and water passes through the gap H1. The ratio (H1 / H) of the height H from the bottom T of the dam body 11 of the transmission type dam structure 10 to the gap H1 is preferably about 0 to 0.2.

  As described above, the transmission-type dam body structure 10 can be installed on the water bottom T. In addition, the some blocks 31-33 of the bank 11 are connected and integrated by the connection members 30a and 30b like FIG. 1 (a) (b).

  Next, the wave-dissipating performance of the above-described transmission-type dam structure 10 will be described with reference to FIGS. FIG. 4 is a cross-sectional view similar to FIG. 3 for explaining a normal flow of water in the transmission-type dam structure of the present embodiment. FIG. 5 is a cross-sectional view similar to FIG. 3 for explaining the force applied during a storm and the flow of water in the transmission type dam structure of the present embodiment.

  As shown in FIG. 4, in normal times, the transmission type dam body structure 10 achieves wave quenching due to the following energy loss.

  (1) Energy loss due to breaking wave due to wave overtopping of incident wave from offshore side

  (2) Energy loss due to turbulence due to outflow water b and inflow water c in the slope slit 22 of the slope wall 14

  (3) Energy loss due to vortices d and e generated in opposite directions by the respective openings of the intermediate slit 24, the rear slit 23, and the bottom plate opening 26.

  (4) Energy loss due to collision between the overtopping wave f and the rear slit 23 at the top of the rear wall 16

  (5) Promotion of energy loss effect due to vortices d and e by facilitating outflow / inflow of water inside the dam body 11 by openings 25 and 26 of the top plate 19 and the bottom plate 20

  The above-mentioned energy loss effects can synergize to promote wave-dissipation, improve the wave-dissipating performance, and reduce both the front reflectance and the rear transmittance. In addition, a transmission type sea area control structure can be realized.

  In addition, by providing a difference between the opening ratio of the front slit 21 + slope slit 22 of the levee body 11 and the opening ratio of the rear slit 23, it becomes difficult for the water at the time of the wave to flow out from the inside of the dam body, and the front and rear surfaces of the dam body As a result of the difference in water level, a jet flow is generated from the inclined slit 22, energy is lost, and wave extinction can be promoted.

  Further, during a storm as shown in FIG. 5, in the bank body 11 of the transmission type bank body structure 10, water passes in the horizontal direction g between the bottom plate 20 and the bottom of the water, and upwards the bottom plate opening 26 of the bottom plate 20. Passing through h, passing through the top plate opening 25 of the top plate 19 in the upward direction j, overtopping the slope wall 14 in the direction i, while applying a horizontal force K, a lifting pressure L, and a vertical downward force M. Among these, the lifting pressure L can be reduced by escaping upward through the relatively large openings 25 and 26 of the top plate 19 and the bottom plate 20.

  Next, a transmission type sea area control structure configured by arranging two transmission type bank structures 10 of FIGS. 1 to 3 will be described with reference to FIGS. 6 and 7. FIG. 6 is a front view of a transmission type sea area control structure in which two transmission type bank structures 10 of FIGS. 1 to 3 are arranged side by side. FIG. 7 is a front view of a transmission type sea area control structure in which two conventional transmission type bank structures are arranged side by side.

  As shown in FIG. 6, the transmission type sea area control structure 50 is configured by arranging at least two transmission type dam body structures 10 shown in FIGS. . At this time, the protruding portions 43a, 43b, 43c of the overhang structures 41, 42 of the respective dam bodies 11 are close to each other, so that the interval W1 between the dam bodies 11, 11 is narrowed and the openings 43, 44 are respectively formed. New opening slits 51 and 52 are formed by being close to each other by two. In addition, in the depth direction of each levee body 11, as can be seen from FIGS. 2A and 2B, the openings formed by the protruding portions 46 are integrated in the middle to form new openings, and the rear surface. In FIG. 5, the openings formed by the protrusions 47 are integrated to form a new opening. With the new opening slits 51 and 52 that are integrated with each other, the wave-extinguishing structures 41 and 42 can exhibit a wave-absorbing property.

  Furthermore, by the at least two adjacent arrangements of the transmission type dam body structure 10, the opening portions 45, 45 on the bottom plate side are close to each other in the horizontal portion of the overhang structures 41, 42, respectively, so that a new one is formed. An opening is formed, and two openings 48 on the top plate side are close to each other so that a new opening is integrally formed. Thereby, in the overhang structures 41 and 42, the area of the horizontal portion can be reduced, and it can be reduced by releasing the lifting pressure L (FIG. 5) applied to the horizontal portion. There is no fear, and there is no need to increase the dimension such as the thickness of the member. Thus, even if the overhanging structures 41 and 42 are provided on the dam body 11, it is possible to prevent the possibility of member destruction due to lifting pressure.

  In the transmission type sea area control structure 50 in which two transmission type bank structures 10 described above are arranged, as shown in FIG. 6, the foundation pile 29a of the transmission type bank structure 10 and the adjacent transmission type bank structure 10 The interval W2 between the object 10 and the foundation pile 29b is relatively wide because the overhang structures 41 and 42 exist between the two levee bodies 11 and 11. That is, as shown in FIGS. 1A, 1C, and 1D, the foundation piles 29a and 29b are in a positional relationship in which the horizontal position in the horizontal direction in the figure is relatively shifted inward by the overhang structures 41 and 42. The space W2 between the foundation piles is widened by the provision of the overhang structures 41 and 42. Similarly, the interval W2 between the foundation piles 29c and 29d is increased by the provision of the overhang structures 41 and 42.

  As shown in FIG. 7, according to the prior art, when the interval W1 between the levee bodies B1 and B2 is reduced, the interval W2 between the foundation piles C1 and C2 is also reduced, and interference between the piles is inevitable. On the other hand, according to the transmission type sea area control structure 50 of the present embodiment, even if the interval W1 between the dams 11 and 11 is narrowed, the interval W2 between the foundation piles is caused by the overhang structures 41 and 42 as shown in FIG. Become wider. Thus, by making the side surface of the levee body overhang, the interval W1 between the levee bodies can be narrowed, interference between the foundation piles can be avoided, and the amount of scouring around the foundation pile can be reduced. can do. Further, by reducing the distance between the bank bodies, the transmittance is not increased, and therefore the width of the bank body per box is not increased and the structure of the bank body is not increased.

  As mentioned above, since interference between foundation piles can be avoided, the bearing capacity of the piles does not decrease, there is no need to increase the pile penetration length, and the pile penetration length is increased. It is possible to prevent deterioration in economic efficiency and workability due to the fact that the scouring amount of the ground G around the foundation pile is not increased and the periphery of the pile is not greatly scoured. The bearing capacity is not reduced, and the stability of the pile can be maintained.

  The dimensions of the transmission type sea area control structure in FIG. 6 are, for example, the width of the levee body: 8.7 m, the distance W1 between the dam bodies: 0.4 m, and the distance W2 between foundation piles: 4 m. Moreover, the dimension of FIG. 7 is the width | variety of a levee body: 8.4m, the space | interval W1: 0.8m of a levee body, and the space | interval W2 between foundation piles: 2.4m, for example.

Experimental example

  Next, in order to confirm the effect of the present invention, a two-dimensional moving bed experiment was performed to compare the scouring amount (depth) around the foundation pile. FIG. 8 shows an outline of the experimental apparatus used in this experiment. In this experiment, a 1/30 scale model using two levee bodies similar to FIG. 6 is used, and a 1/30 scale model using two dam bodies similar to FIG. 7 is used as a comparative example. It was. The specifications of the sand used and the wave conditions are as shown in Table 1 below.

実験例及び比較例について、波浪条件を現地換算で有義波高（Ｈ_1/3）＝２．００ｍ、有義波周期（Ｔ_1/3）＝１３．９ｓとした場合の洗掘深さの測定結果を図９に示す。同様に、波浪条件をＨ_1/3＝５．７１ｍ、Ｔ_1/3＝１３．９ｓとした場合の洗掘深さの測定結果を図１０に示す。

For the experimental example and the comparative example, the scouring depth when the wave condition is significant in terms of significant wave height (H _1/3 ) = 2.00 m and significant wave period (T _1/3 ) = 13.9 s The measurement results are shown in FIG. Similarly, FIG. 10 shows measurement results of the scouring depth when the wave conditions are H _1/3 = 5.71 m and T _1/3 = 13.9 s.

  According to this experimental example, in both cases of FIG. 9 and FIG. 10, both the average scouring depth and the maximum scouring depth are smaller than the comparative example. It was confirmed that the amount of excavation can be reduced.

  As described above, the modes for carrying out the present invention have been described. However, the present invention is not limited to these, and various modifications can be made within the scope of the technical idea of the present invention. For example, in order to reduce the area of the horizontal portion in the overhang structure, in the present embodiment, a small number of relatively large openings are provided in the bottom plate and the top plate in the overhang structure, but the present invention is not limited thereto. A large number of small openings may be provided.

  Moreover, when the transmission type sea area control structure 50 in FIG. 6 is actually constructed in a water area, a large number of the transmission type bank structure 10 in FIGS. 1 to 3 are arranged according to the required length. .

  In addition, a front slit 21, a slope slit 22, a rear slit 23, and an intermediate slit 24 are provided on each wall portion (front wall 13, slope wall 14, rear wall 15, intermediate wall 16) in the dam body of this embodiment as shown in FIG. However, each aperture ratio may be adjusted by using another embodiment. For example, in the example of FIG. 14, the number of each of the front slit 21, the rear slit 23, and the intermediate slit 24 is increased as compared with the case of FIG.

  In the example of FIG. 15, the number of front slits 21, rear slits 23, and intermediate slits 24 is increased from that in FIG. 3, and the positions of the rear slits 23 and intermediate slits 24 are changed from those in FIG. 14. Further, the upper wall portion 16a (FIGS. 3 and 14) of the intermediate wall 16 is omitted, and an intermediate slit 24 is provided at the position of the wall portion 16a.

  Further, in the example of FIG. 16, the positions of the rear slit 23 and the intermediate slit 24 are the same as those in FIG. 15, but the number of front slits 21 is the same as in FIG.

  In addition, the number of foundation piles in the transmission type levee structure shown in FIGS. 1 to 3 may be increased in accordance with the supporting load, the pile diameter, etc. In this case, the interval between the foundation piles does not cause scouring. Is preferably set sufficiently long.

DESCRIPTION OF SYMBOLS 10 Transmission type bank body structure 11 Bank body 12 Foundation structure 13 Front wall 14 Slope wall 15 Rear wall 16 Middle wall 17, 18 Side wall 19 Top plate 20 Bottom plate 21 Front slit 22 Slope slit 23 Rear slit 24 Middle slit 25 Top plate opening 26 Bottom plate openings 29a, 29b, 29c, 29d Foundation piles 31, 32, 33 Split blocks 41, 42 Overhang structures 43, 44 Openings 45, 48 Openings 50 Transmission type sea area control structures 51, 52 Opening slit L Lifting pressure W1 Spacing between dam bodies W2 Spacing between foundation piles

Claims (6)

A permeable embankment that includes a wall portion having an opening and a horizontal portion and exhibits wave-dissipating performance, and a foundation structure composed of a foundation pile driven into the ground from the bottom of the water to support the dam body, A permeable embankment structure comprising:
The levee body is provided with a projecting structure projecting outward from the side surface with respect to the horizontal position of the foundation pile, and the area of the horizontal portion in the projecting structure is reduced. The horizontal portion has a bottom plate and a top plate,
The transmission type levee structure according to claim 1, wherein openings are provided in the bottom plate and the top plate in the overhang structure. The wall portion of the bank body has a front wall and a slope wall on the front side,
The transmission type levee structure according to claim 1 or 2, wherein openings of complementary shapes are provided in the front wall and the slope wall in the overhang structure, respectively. A transmission type sea area control structure configured by arranging at least two transmission type levee structures according to claim 1,
When the levee bodies of the at least two permeable type dam body structures are arranged so that the sides face each other and approach each other, the foundation piles of the respective permeable type dam body structures are separated in the horizontal direction by the overhang structure. A transmission-type sea area control structure characterized by A transmission-type sea area control structure configured by arranging at least two transmission-type dam structures according to claim 3,
When the levee bodies of the at least two permeable type dam body structures are arranged so that the side surfaces face each other and approach each other, the foundation piles of the respective transmissive type dam body structures are separated in the horizontal direction by the overhang structure. The transmission type sea area control structure is characterized in that the openings of complementary shapes of the front wall and the slope wall in the projecting structure are integrated to form a new opening.   A partition block for a bank body, wherein the bank body of the transmission type bank body structure according to claim 1 is divided into a plurality of blocks so as to be separated in a vertical direction.

Images