JP2006125102A - Block for shore - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate piling and additional piling of wave dissipating concrete blocks, and to prevent the blocks from being moved by wave force. <P>SOLUTION: The wave dissipating concrete block 1 is trapezoidal in section, and provided with a recessed part 2 formed at the base, to which the upper part 21 of the wave dissipating concrete block 1 can be fitted. The wave dissipating concrete block 1 having a through hole 3 directed from the upper side to the base is laid while the sea bottom is flattened, and after the completion of laying for the first stage, the recessed part 2 of the base is fitted in the upper part 21 of the wave dissipating concrete block 1, and the blocks are piled for the second and following stages installed to thereby form a wave-absorbing breakwater where the blocks are firmly connected to each other. Even when the wave-absorbing breakwater is sunk or the sea water level is raised, it will be sufficient to fit the recessed part 2 to the upper part 21 of the existing block, so that additional piling can be facilitated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a coast block for protecting a coast requiring wave control or sand drift control.

  Wave-dissipating blocks used as a means of wave-dissipating waves against the coast have been proposed in various shapes, but as shown in FIG. 9, protruding legs such as blocks with protruding legs and cross-shaped blocks are not used. The blocks that had them were piled up with their legs engaged to construct a breakwater.

  However, since the conventional wave-dissipating blocks are constructed by randomly engaging the blocks with each other to build the dam body, they cannot be stacked in an aligned state, and the blocks sink or the sea level rises. When it was necessary to add more, it could not be simply stacked upwards, and it took time and money. In addition, the block generally does not have a flat bottom surface, and the area of the relatively long and slender projecting leg portion that contacts the sea bottom or mound tends to be small, and the ground pressure tends to increase.

Patent Document 1 (Japanese Patent No. 2649338) provides a leg portion bent downward at a substantially right angle from two corner portions of a triangular main body, forms a connecting portion from the remaining corner portion, and at its end portion A stable part is formed orthogonally.
In Patent Document 2 (Japanese Patent No. 2690463), a front wall and a rear wall, which are spaced apart from each other with a predetermined interval in the front-rear direction, are connected and integrated by an upper beam and a lower beam that are three-dimensionally crossed in an X shape in plan view. A water guide hole penetrating in the front-rear direction is provided at the center of the front wall.
Patent Document 3 (Japanese Patent No. 2847339) is a hollow wave-dissipating block that is used by being horizontally placed in a state where it is always submerged under the sea surface. A plurality of openings are provided so as to have an opening ratio of ˜25%. However, it is basically a box type and does not have a meshing portion, so it is not assumed to be stacked, and is independent. It is intended only for use.
Japanese Patent No. 2649338 Japanese Patent No. 2690463 Japanese Patent No. 2847339

When moving or sinking due to the force of waves, the shape of the installation of the wave-dissipating blocks will not be maintained, so it was necessary to add or restore the wave-dissipating blocks in order to return to the original stacked state. .
On the other hand, a wave-dissipating block with a flat bottom surface does not have a meshing part, so there is no means for firmly connecting each other even when stacked, and it moves easily by wave energy, so It could not be a dam body.
It is an object of the present invention to facilitate stacking and to prevent the stacked upper and lower blocks from firmly moving so as not to move even by wave force.

A wave-dissipating block that has a trapezoidal cross section, has a fitting recess that accommodates the upper part of the trapezoid on the bottom surface, and has a through hole that leads from the top surface to the fitting recess.
Moreover, it is a wave-dissipating block in which a through hole is formed between a through hole that communicates from the side surface to the fitting recess and the side surface.

  Since the ground contact area of the wave-dissipating block is relatively larger than that of the conventional wave-dissipating block, subsidence does not occur, and even when the wave-dissipating block sinks or moves, The wave-absorbing function can be restored easily.

EXAMPLES The present invention will be described based on illustrated examples.
As shown in FIGS. 1 and 2, the wave-dissipating block 1 is made of unreinforced concrete and has a trapezoidal shape with a cross section of 0.5 m on the upper side, 2.5 m on the lower side, and 2.0 m on the hypotenuse, and a trapezoidal recess on the bottom side. 2 is formed, and the concave portion 2 has such a size that the upper portion 21 of the wave-dissipating block 1 is fitted, and can be stacked in order.

  Holes 3 having a diameter of 10 to 20 cm passing through the recess 2 formed on the bottom surface from the upper side of the wave-dissipating block 1 are formed at substantially equal intervals, and the lifting pressure acting on the bottom surface of the wave-dissipating block 1 is reduced. Moreover, the through-hole 31 is formed between the through-hole 31 which leads to a fitting recessed part from a side surface, and a side as needed.

As shown in FIG. 3, the wave-dissipating block 1 is laid side by side on a mound constructed on the seabed, and when the first-stage laying is completed, the concave portion 2 on the bottom surface is fitted into the upper part 21 of the wave-dissipating block 1. The second and subsequent stages are stacked and installed as a breakwater.
The arrangement and stacking of the wave-dissipating blocks 1 can be variously installed as shown in FIG.

If the breakwater has sunk due to the weight of the breakwater and the impact of waves, the new breakwater block is placed on the topmost breakwater block. It can be placed and can be easily restored to its original state.
In addition, when the sea level rises due to the effects of global warming, etc., the top position of the breakwater built by the wave-breaking block cannot maintain the predetermined relationship with the seawater surface, and the wave-dissipating performance is affected. However, it is easy to stack additional wave-dissipating blocks and can be easily recovered.

Application Example When an artificial reef (submarine) is installed along the coast, the water level rises behind the structure due to the water flow over the artificial reef as shown in FIG. For this reason, the flow returning to the offshore side from both sides of the structure becomes dominant, local scouring occurs on the shore side, and it is difficult to maintain a stable beach even if beach nourishment is performed on the shore side. The block of the present invention can also be used as sand drift control.

  As shown in FIGS. 5 and 6, the blocks 1 are laid on the seabed. The inclination of the trapezoidal block 1 and the water flow interfere with each other, and a vortex is generated on the inclined surface. The vortex rises along the surface and becomes an offshore flow on the structure. To compensate for this offshore flow, a shoreward flow occurs on both sides of the structure, facilitating sand movement from the offshore to the shore. As a result, sand drift is accumulated and coastal erosion can be prevented. Moreover, since the flow toward the offshore also cancels the energy of the waves arriving from the offshore, it can be a stable beach that prevents coastal erosion.

  As another application example of the wave-dissipating block of the present invention, as shown in FIG. 8, the wave-dissipating block 1 of the present invention is stacked on one or more stages on the front wall of an upright revetment 4 using caisson or the like. It can also be used to prevent direct collision with the structure. Furthermore, it can be used as a revetment, adjacent to an inclined surface, or used for covering a rubble mound of an artificial leaf. As described above, since there are various installation modes of the wave-dissipating block, the way of stacking is selected in consideration of natural conditions such as harmony with the surroundings as a landscape and wave power.

As described above, according to the present invention, since the recessed portion is formed on the bottom surface with a trapezoidal cross section, the recessed portion and the upper side portion can be meshed and sequentially stacked to be integrated as a breakwater. Easy to reload. In addition, holes penetrating from the top surface to the bottom surface are formed at substantially equal intervals from the upper side or side surface of the wave-dissipating block to the recess of the bottom surface, reducing the lifting pressure acting on the bottom surface of the wave-dissipating block, and eliminating the Prevent wave block movement.
Furthermore, the hole which penetrates the side surface of a wave-dissipating block provides the environment as a place for growth of living things.

The perspective view and sectional drawing of the Example of this invention. The perspective view and sectional drawing of the other Example of this invention. Sectional drawing of the breakwater using the block of this invention. Sectional drawing which shows the aspect of the arrangement | sequence of the block of this invention. Sectional drawing explaining the flow of water at the time of using the block of this invention for sand drift control. The top view explaining the flow of water at the time of using the block of this invention for sand drift control. The top view explaining the coast erosion by the conventional coast structure. Sectional drawing of the revetment using the block of this invention. Explanatory drawing of the usage example of the conventional wave-dissipating block.

Explanation of symbols

1 wave-dissipating block 2 fitting recess 3 hole

Claims (2)

A coastal block having a trapezoidal cross section, a bottom surface formed with a fitting recess that accommodates a trapezoidal upper portion, and a through hole that leads from the top surface to the fitting recess. The coast block according to claim 1, wherein a through hole is formed between the side surface and the through hole communicating with the fitting recess from the side surface.

Images