JPS5883711A - Construction work of offshore breakwater - Google Patents

Abstract

PURPOSE:To obtain effectively wave-braking effect by a method in which piles are vertically driven in zigzag down to stable ground under water, blocks are stacked up on the supporting parts of the piles, and the piles are connected with each other. CONSTITUTION:Piles 1 are vertically driven in zigzag down to stable ground under water, and flange-like supporting parts 2 are fixed to the piles 1. Then, connecting blocks 3 are fixed in zigzag onto the piles of front and rear rows to construct the lower constitutions of front and rear rows. Blocks 5 for breaking wave and blocks 4 for adjust are inserted into the piles 1 to connect the piles of front row with the piles of rear row to form spaces into which the sea water is to be introduced. Interrupting blocks 6 and 7 and the connecting blocks 3 are then placed on the piles 1 of front and rear rows to construct wave-reflecting sections. Thus, tidal wave is damped, refracted, and discharged from the spaces on the onshore side, whereby effectively performing the breaking of tidal wave.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a construction method for offshore breakwaters used for coastal erosion prevention and wave dissipation.

Conventional wave-dissipating breakwater breakwaters, which are used to prevent coastal erosion, are built by building a foundation on the seabed, stacking irregularly shaped blocks on top of it, and using the weight of the blocks to counteract waves and reflect them. This method allows some of the waves to pass through the breakwater, diffracts the waves from both ends of the breakwater to the land side, and returns the decelerated waves to the offshore side.

With this method, the height cannot be increased unless the bottom is made wider as the water gets deeper. Since irregularly shaped blocks of a certain size are simply piled up, it is necessary to stack them to stabilize them, and it is necessary to increase the number as you go down. Therefore, unless the number of blocks is increased geometrically, it will not be stable and the height will not increase, so the deeper the water gets, the wider the bottom needs to be. The number of blocks increases accordingly, making it more expensive. Furthermore, since conventional offshore breakwaters are installed on the seabed and supported by their weight, there is a risk that the installed area will be washed away by waves and collapsed, so countermeasures are also required.

The present invention eliminates this conventional drawback and theoretically, safely,
This construction method was designed to install offshore breakwaters at low cost.

The configuration of this invention will be explained with reference to the drawings.

FIG. 1 shows an example of the configuration of the present invention.

As shown in the figure, multiple piles are driven in a staggered manner up to the maintenance plate. These piles have theoretical conditions such as thickness, length, and thickness depending on the natural conditions of the installation site and other necessary conditions. A flange-like object as shown in Fig. 2 is fixed, and serves as an underwater point to stop the block near the depth of the seabed. If this position is not level depending on the location, insert a lyre from above through the stakes and adjust. If the underwater points are not level on each stake, insert a lyre from above through the stakes and adjust each Make sure that both the stakes and the underwater points are horizontal. Next, as shown in FIGS. 1 and 2, the front row piles and the rear row piles are connected by inserting blocks 3 through the piles at different levels to form the lower parts of the front and rear rows. Next, blocks 4 and 5 are installed through piles to connect the front and rear rows and to form a space for introducing seawater. Next, blocks 6, 7, and 3 are installed through the stakes as shown in FIG. 1 and FIG. 2 to form a part that reflects waves.

Next, something like mortar is placed between the blocks and the piles to secure them in place. If the pile is a steel pipe pile, put mortar or other material inside the pile to secure it.

The structure created in this way has both a rigid frame structure and a truss structure with the front and rear piles, making it a cooperative structure.

Even when the water depth increases, there is little change in the width, and only a small amount of blocks need to be added to the depth. In terms of effectiveness, the upper part reflects waves, and the waves that enter from the lower space are attenuated by the block 5, diffracted, and discharged from the space on the land side. Space-based wave dissipation and diffraction can be performed in the same place, so it does not take up much space. Moreover, since the upper part between the front row and the rear row is open, there is enough room for the waves to push up from the lower part, and the wave-dissipating ability of this space is maximized, which is theoretically ideal. This means that we can expect a wave-dissipating sedimentation effect that can be calculated.

This is much more advantageous than the conventional method of diffracting the coast from the space at both ends of the breakwater. The structure contradicts the conventional wisdom that it is difficult to pull sand back in the case of a continuous levee. Moreover, since the superstructure is supported by piles and the piles are driven into stable ground, there is no need to worry about washing away by waves as with conventional construction methods.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the structure of this invention Fig. 2 is a front view of the front row of this invention Fig. 3 is a plan view of this invention Fig. 4 is a side view of this invention Fig. 5 is a block support of this invention Piles with members attached Fig. 6 shows the shape of each block of the present invention; Wave connecting blocks 6, 7...Interrupting block patent applicant Hisato Owaki (1 other person)

Claims (1)

[Claims] 1. Drive piles vertically in a staggered manner to stable ground underwater, create fixed points at predetermined positions underwater, and use this fixed point as a base to pile up blocks of various shapes depending on the purpose.
The front and rear piles are restrained with blocks to create a rigid frame structure, the upper part is closed with blocks to reflect waves, the waves are introduced from the lower space, and the waves are dissipated and decelerated by hitting the blocks that connect the front and back of the piles. A method of constructing an offshore breakwater that drains waves from the space.