JPS603309A - Concrete block for revetment and revetted levee therewith - Google Patents

Abstract

PURPOSE:To prevent the scouring and sucking phenomena to be encountered in the frontal area of a levee by a method in which concrete blocks having a water storing section to temporarily store the tidal waves beating upon the shore are set, and the flow of reflection waves is changed to steady flow by means of the water storing section. CONSTITUTION:The tidal wave of sea water is temporarily stored by a water storing section 11 formed of a flat bottom plate 1, a wave-breaking plate 2, and a wall plate 7 right-angled t these plates 1 and 2. Since the opposite side of the wall plate 7 is open, the sea water flows out gradually from one end of the bottom plate 1 at the same time as the tidal waves ebb. The energy of reflection waves is greatly damped, combined with the wave-dessipating effect due to the wave-dessipating plate 2, and a gentle flow like steady flow results. Since the water storing section becomes empty at the time when the next tidal waves come up, the sea water can be stored as in the previous case. The amount and energy of the sea water waves rising on the levee can thus be greatly reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to concrete blocks for seawalls and seawalls using the same, and more specifically, the present invention relates to concrete blocks for seawalls and seawalls using the same. This invention relates to a concrete block for a seawall for constructing a permanent seawall, which prevents scouring and suction phenomena at the front of the bank body by bringing the flow of reflected waves close to a steady flow, and a seawall using the concrete block.

Accidents frequently occur in which seawalls, which have traditionally been built on sandy beaches to prevent coastal erosion, are damaged or damaged. This is due to strong reflected waves scouring the front of the embankment foundation, and interstitial water within the embankment colliding with the concrete of the embankment. Together with the strong reflected waves, water passing through the narrow gaps between the embankments and sand is sucked out to the front of the embankment. It is empirically known that this is due to the suction phenomenon.

Therefore, a method of covering the front wall with glue was adopted, which can withstand some amount of suction and can stand on its own and continue to function even if some soil flows out from the back. The butt wall type has a wide bottom plate and a slope of 1:0.5 to withstand scouring at the front of the embankment.
It is quite large. However, in this buttress type seawall, the energy of the reflected waves is not attenuated very much, and the sandy beach is significantly receded, and the front surface is scoured and sucked out by the reflected waves, resulting in a constant risk of damage, collapse, etc.

The present inventor believes that these seawalls are all made of strong concrete, but they have a large amount of energy), so they do not have a strong wall to protect against the waves that hit the coast, but rather attenuate the wave energy. 1 In particular, we focused on the fact that a seawall that weakens the energy of reflected waves and allows free flow of pore water at the back of the embankment body is stronger as a result.
The present invention was completed by covering the embankment body with concrete blocks having a large number of water storage tanks that temporarily pool seawater that washes up with the waves and slowly releases it until the next wave.

That is, the present invention aims to provide a permanent seawall by breaking waves and turning reflected waves into a gentle steady flow to prevent front surface scouring. Concrete blocks for seawalls in which a wave-breaking plate planted in the bottom plate and one wall plate perpendicular to the bottom plate and the wave-breaking plate are integrally cast, and a large number of such concrete blocks for seawalls. This is a seawall with a wave-breaking plate facing toward the ocean and a bottom plate placed in close contact with the slope.

The concrete block according to the present invention requires that a strong bottom plate, a wave breaking plate, and a wall plate are cast integrally. The bottom plate is flat so that it can be placed stably on a slope, and the wave breaking plate is preferably a sturdy one that is slightly inclined toward the bottom plate so as to withstand wave energy. The wall board is installed perpendicularly to the bottom board,
When constructed on a slope, it is desirable that the top surfaces of the bottom plate and wave-breaking plate be horizontal. As a result, a water tank is formed by the bottom plate, wave breaking plate, and wall plate, and becomes a container for storing seawater, but because one wall plate is missing, the water cannot be stored for a long time, and as the waves recede, one of the bottom plates It gradually flows out from the edge, and the energy of the reflected waves is significantly attenuated by the wave-breaking effect of the wave-breaking plate, resulting in a slow flow similar to a steady flow, and the water tank is empty before the next wave hits. , the following seawater can be stored.

Hereinafter, the present invention will be described in detail by way of examples with reference to the drawings.

FIG. 1 is a perspective view of a concrete block.

1 is a bottom plate, 2 is a wave breaking plate planted on the bottom plate 1, a part of the bottom face 3 extends to the external force of the bottom plate, and forms a recess 5 with the first end 4 of the bottom plate. Number 6 is a curved wave breaking surface, which receives waves and attenuates energy. A wall plate 7 is formed integrally with the wave breaking plate 2 at a third end 8 adjacent to the first end 4 of the bottom plate 1. 9. Second end of bottom plate ￥1I
11o, which is longer than the outwardly extending portion of the bottom surface of the wave-breaking plate 2 (and has a size that can be fitted into the four parts 5 of other blocks of the same shape. Therefore, the wall plate 7 is It is provided deeper than the insertion part 9. Although the shape of the wall plate is not limited, it is inclined from the bottom plate surface toward the upper end of the wave breaking plate 2,
If possible, it is desirable that the surface formed by the upper end of the wave breaking plate 2 and the upper end of the wall board 7 be horizontal when this block is constructed on a slope. A recessed water tank 11 is formed by the bottom plate 1, the wave breaking plate 2, and the wall plate 7. 12
is a drainage channel forming part formed by extending the fourth end 13 of the bottom plate outward from the wave breaking plate, and forms a drainage channel through which seawater temporarily stored in the water storage tank 11 flows out before the next wave. do.

FIG. 2 shows another embodiment in which the drainage channel forming portion 12 is provided outside the wall plate 7 and the wave breaking surface 6 is made flat. In any of the above embodiments, the slope surface is completely covered by the bottom plate, but since the bottom plate and the bottom plate are not bonded to each other, the gap water behind the embankment body can freely pass through. Since the fitting part 9 of another block is inserted into the block and assembled, the bottom plate has the advantage that it is difficult to shift.

Figure 3 is a layout diagram of a sea wall using the concrete blocks of the present invention, viewed perpendicular to the slope, and Figure 4 is IV-I of Figure 3.
It is a sectional view taken along the V line. 14 is the slope, and 15 is the foot protection work. Waves crashing from the ocean first collide with the breaking wave surface 6a and break mechanically, and a portion of the 7h water is stored in the water storage tank 11a. The remaining waves are further broken on the wave breaking surface of the two-stage block 6
b and breaks into pieces, and a portion is stored in the water tank 11b. In this way, as the N'r5 water rises to the upper level, the amount of seawater decreases significantly and the wave energy also attenuates. When the waves recede, the seawater stored in the water tank 11 flows down from the side where the wall plate 7 is not provided, passes through the drainage channel 16, enters the lower water tank 11, and further flows down the drainage channel 16. In this way, the reflected waves cannot flow down all at once, so they are attenuated and become close to a steady flow, so there is no scouring of the front surface of the levee body, and there is no suction from the back surface of the levee body. Even if it were to be sucked out, the bank protection block covering slope CI according to the present invention has the flexibility to be transformed into a slightly depressed slope, so it will not lead to the destruction of the embankment body.

In this embodiment, the drainage channel 16 is formed on the bottom plate, but in some cases, the drainage channel forming part 12 is not provided on the concrete 1-block itself, and the concrete blocks are arranged to maintain the interval between the drainage channels. It's okay.

Drainage channels must be wide enough not to be blocked by shellfish, etc.
The length is 10-40 cm, preferably 15-30 cm. Further, when the blocks of the present invention are arranged on a slope, in this embodiment, the upper and lower stages are arranged side by side, but it is not necessary to stagger them, and a drainage channel running perpendicularly may be used.

As described above, according to the present invention, the amount and energy of wave seawater rising up the embankment body is drastically reduced by using the concrete block water tank and the wave breaking plate that cover the slope, and the energy of the reflected waves is not only small, but also The flow is close to a steady flow, and a permanent seawall can be obtained without the risk of scouring the front of the embankment body.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIGS. 1 and 2 are perspective views of concrete blocks for seawalls, FIG. 3 is a layout of blocks viewed from the vertical direction of the slope, and FIG. FIG. 3 is a sectional view taken along the TV-TV line in FIG. 3; In the drawing, 1 is a bottom plate, 2 is a wave breaking plate, 4 is a first end, 5 is a recess, 6
is a wave breaking surface, 7 is a wall plate, 9 is an inset part, 10 is a second end part,
11 is a water tank, 14 is a slope, 15 is a foot protection work, and 16 is a drainage canal. Patent applicant: Nippon Sohan Co., Ltd. Agent Patent attorney: Sadako Suzuki

Claims (4)

[Claims] (1) Concrete blocks for seawalls, in which a flat bottom plate, a wave-breaking plate planted on the bottom plate, and one wall plate perpendicular to the bottom plate and the wave-breaking plate are cast as one unit. (2) a flat bottom plate; a wave-breaking plate planted on a first end of the bottom plate, a part of the bottom extending outward from the bottom plate, and forming a recess on the bottom surface; At a second end opposite to the end, one wall plate is perpendicular to the bottom plate and the wave breaking plate, leaving a fitting part shaped to fit into the recess formed in the first end. Concrete blocks for seawalls are cast in one piece. (3) A large number of concrete blocks for seawalls are constructed of a flat bottom plate, a wave-breaking plate planted on the bottom plate, and one wall plate perpendicular to the bottom plate and the wave-breaking plate. ,
A seawall with a wave-breaking plate facing the ocean and a bottom plate placed in close contact with the slope. (4) A seawall according to claim 3, wherein a large number of concrete blocks for seawall are arranged with drainage channels formed between wave-breaking plates.