JPH0412331B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a method for pouring sand into the water bottom, which is employed in works such as laying sand, filling sand, and replacing sand in construction work for underwater structures. .

(Prior Art) The inventor of the present application has discovered that the conventional method of directly dropping sand into water causes a large loss of sand, and especially when the water is deep, the amount of sand that far exceeds the required amount is scattered around the area. We have already developed a sand pouring method that solves various disadvantages such as economic efficiency, inability to efficiently lay sand in a specified flat shape, and muddying the surrounding water due to large amounts of sand scattered around. Researched and invented (Special Publication No. 54-23484).

That is, the lower end of the upper pipe is slightly inserted into the upper end of the lower pipe with a larger diameter, and the conduit is connected in several stages so as to form an appropriate gap between the upper end pipe and the lower pipe. Hold the hopper vertically in the water so that the upper end is slightly below the water surface and the lower end is slightly above the water bottom, and insert the lower part of the outlet of the hopper into the upper end of the top pipe of the conduit to create a gap there. The sand fed into the hopper is allowed to fall continuously into the pipe through the discharge port, and as the sand falls, the ejector action opens the upper end of the top pipe and connects each stage. This method of pouring sand into an underwater structure is characterized in that the sand is lowered by being energized by a downward water flow induced to flow into the conduit from the opening of the pipe through the circumferential gap.

(Problems to be Solved by the Invention) As a result of further research tests, the inventor of the present application has found that the above method is sufficiently effective for laying sand in a relatively narrow band or embankment, etc. It was discovered that the ability to flatten, fill, and replace sand over a vast area is not yet perfect in terms of efficiency, workability, stability, and reliability. This is due to the fact that the sand is not lowered over a wide range and evenly (flow rate) from the lower end of the lowermost conduit.

(Means for Solving the Problems) The present invention has been made to solve the above problems, and in the sand pouring method, the inside is divided into a plurality of downflow passages, and the sand pouring passages are divided gradually toward the bottom. An induction hood having a widened portion is provided so as to communicate with the lowermost conduit, and the sand descending from the lowermost conduit is distributed and guided to each of the above-mentioned downflow passages, so that the sand can be guided to each of the downflow passages of the induction hood. To provide a method for pouring sand into a water bottom, characterized in that sand is allowed to fall over a wide range from each opening grill formed by a lower surface at a substantially uniform flow rate.

The present invention will be described in detail below with reference to drawing examples.

First, in Figures 1 and 2, the lower part of the upper pipe is inserted slightly into the upper end of the lower pipe with a larger diameter than that, and an appropriate circumferential gap s is formed between the upper pipe and the lower pipe. A conduit 1 connected by a multi-stage chain 2 is vertically held in water by an appropriate method so that the upper end is slightly below the water surface 3 and the lower end is slightly above the water bottom 16. Further, the lower part of the outlet 6' of the hopper 6 is inserted into the upper end of the uppermost tube of the conduit 1 and held vertically so as to form a circumferential gap s therein. Note 4
is a work boat, 5 is a power winch, and 7 is a frame. Then, the sand continuously thrown into the hopper 6 by the grab 18 of the sand transport ship 17 is made to fall continuously into the conduit 1 through the discharge port 6, and as the sand falls, the ejector action It is known (especially known in the art) that the sand is lowered by being energized by a downward water flow induced to flow into the conduit 1 through the circumferential gap s from the upper end opening of the upper pipe and the openings of the connecting parts of each stage. This is the method invented by Kosho 54-23484).

Next, reference numeral 8 denotes a guide hood which gradually becomes wider downward, and has an upper straight cylindrical part 8a at the upper part and a lower straight cylindrical part 8b at the lower part. It is. In addition to the illustrated shape, the induction hood 8 may have a square pyramid or conical shape, and the shape of the grill formed by each flow path 11 may be selected from various shapes as shown in FIGS. 3 and 4 according to the shape. can. Further, the lower part 9b of each of the partition walls 9 is fixed, but the upper part 9a is tiltable about the pivot 10, and can be moved to the top of each flow path 11, for example, as shown by the chain line in FIG. The opening can be made wider or narrower. At the upper end of the upper part 9a of each of the partition walls 9, a projection screw 14 is provided, which is inserted into a circular arc hole 13 having a pivot shaft 10 bored in the side wall of the guide hood 8 as an axis.
The upper part 9a can be fixed in any position by tightening a nut 15 screwed into the upper part 9a.

Therefore, the present invention provides that the interior has a plurality of downflow channels 1.
An induction hood 8 having a section that is divided into 1 sections and gradually widening downward is provided so as to communicate with the lowermost conduit 1, and the sand descended from the lowermost conduit 1 is transferred to each of the above-mentioned drainage channels. 11, and are configured to descend over a wide range from each opening grille 12 formed from the lower surface of each flow passage 11 of the induction hood 8 at a substantially uniform flow rate.

According to the method of this invention, the construction width is narrow as shown in Fig. 7 and Fig. 8 and 9.
In addition, it is easy to perform both cases of displacement sand, which is deep and requires primary charging (conventional method) and secondary charging (inventive method).

(Effects of the Invention) The method of the invention has the above-mentioned configuration, and allows the flow to descend over a wide area from each opening grille on the bottom surface of the induction hood, which has a portion that gradually becomes wider toward the bottom, at a substantially uniform flow rate. Therefore, it has an outstanding effect of being able to perform flat and even work of laying sand, embankment sand, and replacement sand over a vast area easily, efficiently, easily, and stably with extremely good workability. Further, according to the present invention, there is an excellent effect that even when there is a large tidal current, economical work can be carried out stably without scattering sand around the surrounding area.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a partially cutaway front view of the main part, FIG. 2 is a side view of the same, and FIGS. 3 and 4 are bottom views of an embodiment of the opening grille. ,
FIG. 5 is an enlarged longitudinal sectional front view of the main part, FIG. 6 is a longitudinal sectional view showing the fixing device on the upper part of the partition wall, and FIGS. 7 to 9 are explanatory diagrams of the working construction state. 1... Conduit, 2... Chain, 3... Water surface, 4...
...Work boat, 5...Power winch, 6...Hopper, 6...Discharge port, 7...Frame, 8...Induction hood, 8a...Upper straight cylinder part, 8b...Lower straight cylinder part,
9... Partition wall, 9a... Upper part, 9b... Lower part, 10
... Pivot, 11 ... Downfall path, 12 ... Opening grill, 13 ... Arc hole, 14 ... Thrust screw, 15 ...
Natsuto, 16...Underwater, 17...Sand carrier, 18
...grab, s... circumference.

Claims (1)

[Claims] 1 The lower end of the upper pipe is inserted slightly into the upper end of the lower pipe with a larger diameter, and several stages of conduit are connected so as to form an appropriate gap between the upper pipe and the lower pipe. Hold vertically in the water so that the upper end is slightly below the water surface and the lower end is slightly above the water bottom.
In addition, a conduit is passed through the lower part of the discharge port of the hopper into the upper end of the uppermost pipe to form a gap there, and the sand thrown into the hopper is continuously dropped into the conduit through the discharge port. As the sand falls, it is forced by a downward water flow induced to flow into the conduit through the circumferential gap from the upper end opening of the top pipe and the openings of each stage connection part by the ejector action. In a method for pouring sand into an underwater structure, which is characterized by lowering sand, an induction hood whose interior is divided into a plurality of flow passages and which gradually widens downward is attached to the lowermost conduit. The sand descending from the lowermost conduit is dispersed and guided into each of the above-mentioned downflow channels, and the sand is distributed in a wide area at a substantially uniform flow rate from each opening grill formed by the lower surface of each of the downflow channels of the induction hood. A method for pouring sand into the water bottom, characterized by making the sand descend to the bottom of the water.