JPH02204515A - Movable type cam plate wave-breaker - Google Patents

Abstract

PURPOSE:To execute at a low cost by pivotally securing around a horizontal shaft an end of a movable plate body equipped with air chambers on a foundation base placed on seabed, and raising up and bringing down the movable plate body through the supply and discharge of air into and from the air chambers. CONSTITUTION:Air chambers 21 partitioned witch a plural number of walls 22 are provided under a movable plate 2 having resisting members 24 on its surface, and air discharge holes 23 are formed on each air chamber 21, which are opened and closed by remote control. Next, a locking member 25 is installed on one end of a movable plate 2, and other end is pivotally secured around a horizontal shaft 11 on the foundation bed placed on seabed. On the other hand, a lock receiver 12, air discharging holes 13 and cushion materials are installed on the foundation bed 1. The movable plate 2 is sunk by opening the air discharging holes 23, and floated up by supplying air into the air chambers 21 from the air holes 13. This can make execution easy.

Description

[Detailed description of the invention] <Industrial application field> In the present invention, the wave-dissipating swash plate is configured to be able to rise and fall freely;

This relates to a movable swash plate wave dissipating levee that can be used as either a sloping levee or a submerged levee (prior technology). Wave banks have been devised, but each has its own drawbacks.

For example, a submerged levee has a high transmittance for waves other than waves of a specific period, which is affected by the width of the levee body, so it cannot be expected to have much of a wave-dissipating effect.

Slit caisson type breakwaters need to be designed for the predicted maximum probability of waves, which requires a large amount of weight and an excessively large structure, making it impossible to construct on soft ground.

Impermeable caisson type breakwaters prevent the progression of waves, so there is no exchange of seawater inside and outside the breakwater.

Furthermore, the high reflectance of waves makes it difficult to ensure the safety of ships navigating nearby.

Floating breakwaters have high transmittance for long-period waves.

Furthermore, as in the case of a breakwater, it is necessary to use the maximum probability wave as the design wave, resulting in an oversized and expensive structure.

<Objective of the present invention> The present invention was made in order to improve the drawbacks of the various conventional wave-dissipating dykes and breakwaters as described above, and aims to provide the following wave-dissipating levees. shall be.

(a) A wave-dissipating levee that has low reflectance and transmittance during normal waves and can minimize the impact on the inside and outside.During abnormal waves such as a typhoon, a submerged levee is used. A wave-dissipating levee that can protect the structure by reducing the weight of the structure, and a wave-dissipating levee that prevents the structure itself from being damaged by waves. Accordingly, a wave-dissipating levee can be installed even on soft ground without special ground improvement (Configuration of the present invention) Next, an embodiment of the present invention will be described.

<A> Overall structure (FIG. 1) The wave-dissipating levee of the present invention is composed of a base 1 installed on the seabed and a movable plate 2 attached to the base 1 so as to be able to rise and fall.

In order to configure the movable plate 2 so that it can be raised and lowered, a horizontal shaft 11 is arranged at one end of the base IM1, and one edge of the movable plate 2 is attached to the horizontal shaft 11 so as to be rotatable.

<Mouth> Structure of movable plate An air chamber 21 is provided on the lower surface of the movable plate 2.

This air chamber 21 is a box-like structure that uses the movable plate 2 as a ceiling plate, has a wall surface 22 arranged around it, and is open at the bottom.

An exhaust hole 23 for discharging the air inside is provided at the upper part of the wall surface 22 of the air chamber 21.

This exhaust hole 23 is not always open (it can be opened and closed by remote operation).

On the other hand, on the upper surface of the movable plate 2, a long peak-shaped or single mountain-shaped resistance member 24 is provided in parallel with the horizontal axis 11 and protrudes upward.

This resistance member 24 is a member that acts as resistance to water moving on its upper surface.

Furthermore, a locking member 25 for integrally fixing the movable plate 2 to the base 1 is provided on the free end side of the movable plate 2 to project downward.

<C> Base As described above, the movable plate 2 is rotatably attached to one edge of the base 1 via the horizontal shaft 11, and the lock receiver 12 for receiving the lock member 25 of the movable plate 2 is attached to the other edge. will be established.

When the lock member 25 of the movable plate 2 is inserted into the lock receiver 12, the two engage and become integrated.

This lock receiver 12 can be freely engaged and released by operation from a remote location.

A large number of air discharge holes 13 are formed in the upper surface of the base plate 1, and piping is provided to the discharge holes 13 so that compressed air can be supplied thereto.

Furthermore, cushion material 1 is placed on the top surface of the base 1 in several places.
4 is laid so as to be able to absorb the impact when the movable plate 2 and the base 1 come into contact with each other.

<Conversion method between swash plate embankment and submerged embankment> The exhaust hole 23 of the air chamber 21 is closed, and compressed air is supplied into the air chamber 21 from the air discharge hole 13 of the base 1.

Then, the free end of the movable plate 2 floats with the horizontal axis 11 as a starting point, and as a result, a swash plate embankment is formed.

When the exhaust hole 23 is gradually opened, the movable plate 2 sinks quietly and becomes a submerged embankment.

At this time, since the lock member 25 engages with the lock receiver 12 and the two become one, there will be no damage even during abnormal weather such as a typhoon.

<Principle of Wave Dissipation of the Device of the Present Invention> When used as a swash plate embankment, wave dissipation is achieved by transforming incident waves into breaking waves on the slope of the movable plate 2.

In this case, since the movable plate 2 of the present invention has a large number of resistance members protruding from its upper surface, the breaking of the incident waves is further promoted and the loss of incident energy is increased.

Furthermore, the movable plate 2 of the present invention is also characterized in that its rotational motion about the horizontal axis 11 is greatly attenuated.

That is, since the movable plate 2 rotates around the horizontal axis 11,
This rotational motion becomes a wave-making motion, and if left as it is, a large transmitted wave will be sent out.

However, the movable plate 2 of the present invention has a large number of air chambers 2 on its lower surface.
1 is provided, and the compressed air in this acts as a damper, giving a large damping force to the rotational motion, causing the wave-making motion to rapidly attenuate, greatly suppressing the wave height of the transmitted waves. be able to.

Furthermore, in the movable plate 2 of the present invention, the amount of change in buoyancy in the structural cross section that cuts the water line is small.

Therefore, since the restoration spring value of rotation is small, the natural period of rotation of this device becomes long.

As a result, the natural period of the device is longer than the period of the incident wave.

Therefore, the amount by which the device responds to waves can be reduced, and the transmittance can be reduced.

On the other hand, when the movable plate 2 and the base 1 are used by closing them together, the principle is similar to that of a conventional submerged levee, and the water depth suddenly becomes shallower, causing wave breaking or shallow water deformation. will be carried out.

<Effects of the Present Invention> Since the present invention has the above-described structure, the following effects can be obtained.

(a) By raising and lowering the movable plate, it can be used as a sloped embankment or a submerged embankment.

<Exposure> Switching between the swash plate embankment and the submerged embankment can be done simply by supplying and exhausting compressed air, so operation is quick and reliable.

(c) A submerged levee structure can be designed to withstand the maximum probability of waves during abnormal waves, and a swash plate levee can be designed to withstand normal waves.

This has made it possible to significantly reduce construction costs compared to conventional wave-dissipating levees of the same size and size.

<Sheep> Since compressed air is used as buoyancy for the movable plate, this acts as a damper to attenuate the rotational movement of the movable plate, making it possible to reduce the wave height of the transmitted waves.

<PO> The air chamber provided in the movable plate can be installed with its bottom surface open. Therefore, compared to the case where a sealed box is provided, less material is required, and the overall weight can also be reduced.

When used as a swash plate embankment, the restoring force spring can be made smaller to lengthen the natural period of rotation of the movable plate.

Therefore, the response due to incident waves becomes smaller, and the wave height of transmitted waves can be reduced (suppressed).

<G> Since the air chamber provided in the movable plate is composed of a large number of wall plates, it can also be used as a member to reinforce the structure of the movable plate.

Therefore, not only is it economical, but the amount of material used can be reduced and the weight can be reduced.

<H> Since the swash plate levee has a structure that mainly dissipates waves by breaking waves, it is possible to reduce the energy loss and reduce the transmittance against normal waves.

<S> Due to the above-mentioned structural features, the overall weight can be reduced.

Therefore, it can be transported and installed all at once using a 70-ton crane, which reduces on-site work and enables inexpensive installation.

Furthermore, even after it has been installed, it can be easily moved, removed, recovered, repaired, etc. in response to changes in the situation.

Since the overall weight of <Nu> is small, even when installed on soft ground, there is no need for ground improvement or mound production, making it economical to install.

<R> Since both structural members are simple in shape, they do not require large-scale, complicated formwork or scaffolding when manufactured as a reinforced concrete structure, and can be manufactured at low cost.

Furthermore, since most of the work can be completed in a yard on land, quality control is sufficient and a highly reliable device can be obtained.

[Brief explanation of the drawing]

Claims (1)

[Claims] (1) A plate body with one end rotatably attached to a submarine structure on a horizontal axis and the other end not fixed; an air chamber formed on the bottom surface of this plate body with the bottom open; and air in this air chamber. A movable swash plate breakwater consisting of a means for supplying air and a means for exhausting air from the air chamber, and the plate body can be raised and lowered freely.