JPH0223642B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention temporarily stores seawater that washes up on the coast, and provides a shallower water-stopping frame to the box-shaped block that prevents free passage of seawater when the waves recede. In addition to constructing a seawall using concrete blocks, a part of the seawater remains even at low tide, and box-shaped blocks are used to construct a permanent seawall that is suitable for the habitat of coastal organisms. Concerning seawalls.

[Conventional technology]

There have been many accidents in which seawalls, which have traditionally been built on sandy beaches to prevent coastal erosion, are damaged. This is due to strong reflected waves scouring the front of the embankment foundation, and the strong reflected waves flowing down the concrete surface of the embankment as jets sucking out interstitial water in the embankment along with earth and sand from small gaps or cracks in the embankment. It is empirically known that this is due to the so-called suction phenomenon.

The inventor of the present invention discovered that conventional seawalls are all made of strong concrete, but they do not have strong walls to deal with the waves that hit the coast with a large amount of energy, and they are designed to attenuate the wave energy. In particular, we focused on the fact that a seawall that brings reflected waves closer to a steady flow, weakens the energy of scouring at the front of the embankment body, and allows free flow of pore water at the back of the embankment, is ultimately stronger. No. 63-14125, Tokko Akira
No. 63-14126, Japanese Patent Application Publication No. 168805 and Patent Application No. 1983
- In No. 168806, we proposed covering the embankment body with a large number of concrete blocks equipped with wave-breaking plates that temporarily pool seawater that washes up with waves and slowly release it until the next wave.

[Technical problem to be solved by the invention]

However, natural beaches, especially rocky areas, have deep areas where some seawater remains even when the tide is low, and these areas are inhabited by coastal organisms such as shellfish and seaweed, and also serve as hiding places for small fish. The seawall proposed by the present inventor is designed to resemble a natural rocky area as much as possible while ensuring the seawall effect and anti-scouring effect on the front surface of the bank body, and is suitable for the habitat of coastal organisms during low tide. He also conducted research on seawalls in which seawater remains and completed the present invention.

[Means of problem solving]

The present invention is a box-shaped block that stores a portion of the seawater that has washed up on it without letting it flow out until the next high tide by providing a shallow water-stop frame on a concrete block that has a wave breaking board and a drainage channel that constitutes a sea wall. According to the present invention, it is possible to provide a park-like element that allows people to enjoy the seawall at low tide.

The block according to the present invention has a strong bottom plate, a rear wall, a wave breaking plate and a water stop frame which are cast integrally with the strong bottom plate. The bottom plate is sturdy enough to reliably cover the ocean side portion of the sea wall along with the rear wall. The rear wall is installed vertically from the entire rear end of the bottom plate to withstand earth pressure from the back. Furthermore, in order to improve the water storage effect and obtain a sturdy concrete block, the side wall may be provided integrally with the wave breaking plate and the bottom plate.

A part of the wave-breaking plate must be missing, leaving a shallow water stop frame, and this missing part will serve as a drainage channel for reflected waves when a seawall is formed. Although there is no particular limitation on the location where the drainage channel is provided, one end of the front surface of the bottom plate is convenient for manufacturing. Drainage channels must be wide enough to avoid blockage or narrowing due to the proliferation of shellfish, seaweed, etc., and should be at least 70 mm, preferably 100 mm or more.
200mm, sometimes more.

The side wall connecting the wave breaking plate and the rear wall is provided on one side of the box-shaped block as shown in FIG. 1, and only the water stop frame is provided on the other side. In addition, when side walls are not provided, as shown in FIG. 2, a water stop frame is provided to shallowly surround the bottom plate in areas other than the rear wall of the bottom plate and the wave breaking plate. In other words, the water stop frame is shallowly installed in the open part of the bottom plate where no wall is provided, and the water stop frame is shallowly placed to close off the part of the bottom plate where water flows down, and the height of the water stop frame is set at the water storage area for coastal living creatures. This is the depth of

[Effect]

When such blocks are arranged, a drainage channel having the same width as the drainage channel forming portion of the block is formed. The crashing waves successively pass over the breakers from below, consuming energy and reducing the volume of seawater, and when they are pulled back, they are blocked by the breakers and flow down one after another through a narrow drainage channel. Therefore, combined with the wave-breaking effect of the wave-breaking plate, the energy of the reflected waves is significantly attenuated, resulting in a gentle flow similar to a steady flow, and before the next wave hits, it flows out, leaving some of the stored seawater behind, and the next wave washes away. Be prepared for waves. here,
By storing some seawater, it is possible to provide a habitat for coastal organisms.

〔Example〕

1 and 2 are perspective views of a box-shaped block, and FIG. 3 is a sectional view of a seawall using the same. 1 is a bottom plate, 2 is a wave breaking plate planted on the bottom plate 1 leaving a drainage channel forming part 3, and 4 is a side wall provided at the end of the wave breaking plate 2 on the opposite side from the drainage channel forming part 3. 5 is a water stop frame that is much lower than the side wall 4, and the side wall 4 of the wave breaking plate 2
It was installed in the open part on the opposite side. 6 is the rear wall.
As shown in Fig. 1, when the slope is covered in a step-like manner, the outlet for wave seawater is the front part of the wave-breaking plate 2 where the water stop frame is installed, and by shallowly blocking this area with the water stop frame 5, the sea water can be discharged. is stored. 7 is a seawater storage section. Therefore, the bottom plate 1 is surrounded on all sides, and seawater is stored up to the height of the water stop frame 5 at low tide.

FIG. 2 shows another embodiment of the box-shaped block. In this embodiment, side walls 4 are not provided. Therefore, the water stop frame 5 is also provided at the open end where the side wall 4 of FIG. 8 is a stand;
When constructing a seawall using the blocks of this example, from the lower block to the upper block,
Or, if you want to walk in the opposite direction, you can use it as a safe foothold.

FIG. 3 is a perspective view of a seawall constructed using the box-shaped blocks shown in FIG. 2. For turning, the box blocks are lined up side by side in close contact with each other, as shown in FIG. When exposed to waves, the wave-breaking plate 2 attenuates the energy of the waves, and the temporary water storage section 9 stores the waves to reduce the amount of seawater. The undertow is blocked by the wave breaking plate 2 and flows out from the drainage channel 3, approaching a steady flow and preventing scouring of the front surface of the embankment foundation. However, the seawater remaining in the water storage part 7 in the water stop frame 5 cannot flow out, and seawater remains in this part even at low tide, and can be used as a habitat for coastal organisms. 10 is foot protection work. In addition, since the upper ends of the wave breaking plate and the rear wall are horizontal, and the platform 8 is provided in the middle,
You can walk safely inside the sea wall at low tide. Furthermore, seawater remains in the water storage section 7, providing a habitat for coastal organisms and allowing the area to be used as a coastal park.

〔Effect of the invention〕

As described above, with the present invention, seawater remains shallow even when the tide is low, making it suitable for coastal creatures to live in. In addition, the amount and energy of seawater rising up the embankment body is drastically reduced, and the energy of reflected waves is not only small. , the flow is close to a steady flow, and a permanent seawall can be obtained without the risk of scouring the front surface 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 a box-shaped block, and FIG. 3 is a sectional view of a sea wall. In the drawing, 1 is a bottom plate, 2 is a wave breaking plate, 3 is a drainage channel forming part, 4 is a side wall, 5 is a water stop frame, 6 is a rear wall, 7
8 is a water storage part, 8 is a platform, 9 is a temporary water storage part, and 10 is a foot protection work.

Claims (1)

[Scope of Claims] 1. A concrete block having a bottom plate and a rear wall shaped to completely cover the ocean side of a step-like seawall, which concrete block has a structure that allows free sea water to flow when waves recede. A wave-breaking plate that prevents water from passing through is installed integrally from the bottom plate, leaving a drainage channel forming part, and a water-stop frame is installed on the bottom plate to store some of the seawater that has washed up on it without letting it flow out even after the tide has receded. A box-shaped block characterized by the provision of. 2. A concrete block having a bottom plate and a rear wall shaped to cover the entire ocean side of a stepped seawall, and the concrete block is equipped with a wave-breaking plate that prevents the free passage of seawater when waves recede. A box-shaped block is installed on the bottom plate with a water-stop frame that stores some of the washed-up seawater without allowing it to flow out. This is a seawall for coastal living creatures, which consists of lining up the wave-breaking plates with drainage channels left between them, and completely covering the stepped ocean-side slope with the bottom plate and the rear wall.