JP2009041185A - Thin-layer sand spreading equipment and thin-layer sand spreading method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide thin-layer sand spreading equipment and a thin-layer sand spreading method, which are excellent in working efficiency, and which enable a uniform sand layer to be formed on a hardly-checkable sea bottom surface. <P>SOLUTION: This thin-layer sand spreading equipment for forming the continuous thin sand layer comprises: a sand accumulation box 1 which is formed in such an approximate rectangular parallelepiped shape that an undersurface is opened, the internal lower side of which is partitioned into a plurality of sections by a partition, and which is filled with sand in the state of making the four sides of a lower end reach a water-permeable sheet or a water-permeable film, laid on the sea bottom surface; a sand supply body 2 which supplies the slurry-like sand, supplied from on a barge X by a pump P, to the respective sections in the sand accumulation box 1 by making the sand branch off; a discharge body 3 which discharges water, air, fine-grained sand and surplus sand in the sand accumulation box 1 onto the barge X; and a supporting member 4 which is erected in the sand accumulation box 1, and the upper end of which is protruded from a streak groove R formed on the barge X in parallel with the traveling direction of the barge X. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a thin layer sanding apparatus and a thin layer sanding method for applying sand and covering sand to the seabed ground for the purpose of improving the seabed ground.

  In closed water areas such as harbors, pollutants, so-called sludge, have accumulated over many years, and nutrient salts and harmful substances are eluted from them, resulting in poor water quality. Improvement of the water quality is a social requirement. The direct method of improving water quality is to remove the polluted sediment and landfill it in an appropriate disposal site. However, there is a shortage of disposal site compared to the huge amount of contaminated sediment, and the disposal cost This is expensive and difficult to implement. Therefore, in recent years, an economical method of preventing the elution of nutrient salts and harmful substances by covering the surface of the polluted sediment with sand has been implemented.

  In shellfish farms such as clams, even if it has been used for many years, the effects of dead shellfish appear even on sandy ground, and the ground gradually hardens, making it unsuitable for aquaculture. As a countermeasure, a method of spreading sand thinly and evenly, which is more economically advantageous than excavating and improving conventional ground, has been implemented.

  Conventional methods of sanding the bottom of the sea include spraying sand in the hopper on the ship from the sea surface with a belt conveyor, or dropping directly from the sea surface using a gut ship or a bottom-opening ship. There are ways to do it.

  In this method, since the sand is dropped directly from the sea surface or near the sea surface, the seawater tends to become cloudy, so that the surrounding environment is adversely affected. After the turbidity had subsided, it was necessary to measure and manage the thickness of the sand layer, which was very inefficient. In addition, it is difficult to spread sand uniformly from the sea surface or near the sea surface, and it is very difficult to form a uniform sand layer on the sea bottom because it is easily affected by tidal currents before the sand reaches the sea bottom. Met.

The sand-capping device that prevents the thrown-in sand from being affected by tidal currents, etc., uses a sand-spraying chute that reaches a height from the sea to the seabed, and throws sand into the sand-spraying chute from the sea. There is a sand covering device that performs sanding (see, for example, FIG. 1 of Patent Document 1).
If sand is thrown in from the surrounding seawater like this sand spray chute, it will not be affected by tidal currents, but sand is only thrown from the sea, so it is difficult to spread sand uniformly. Also, because a large amount of sand is put into the narrow sand spray chute, the sea water in the sand spray chute is very turbid, and the thickness of the sand layer should be measured and confirmed until this turbidity is settled. It is very inefficient because it cannot.

On the other hand, as a submarine sand dredging device and sand dredging method that suppresses the turbidity of seawater and raises work efficiency, the submarine sand dredging device and sand dredging method that discharges slurry-like sand from the sand dredging head located near the sea bed. (For example, refer to Patent Document 2).
In this submarine sand dredging device and sand dredging method, sand is slurried and pumped with a pump, so there is no need to wait for the sand to settle and work can be done efficiently. Is discharged, so the seawater is less likely to become cloudy and is not affected by tidal currents.
However, the sand trap head that discharges slurry-like sand has a shape whose diameter is enlarged toward the discharge port side, and it is difficult to spread sand uniformly, and the slurry-like sand has a soft bottom. Therefore, it is difficult to stably form a uniform sand layer on the sea floor.

JP 2004-92244 A JP 2000-136533 A

  In view of the above-mentioned problems, the present invention has an object to provide a thin-layer sanding apparatus and a thin-layer sanding method that can form a uniform sand layer on the bottom of the sea that is difficult to confirm and that are excellent in work efficiency. To do.

As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention settled on a water-permeable sheet or a water-permeable film laid on the bottom of the sea on a sand accumulation box having a substantially rectangular parallelepiped shape with an open bottom surface. If slurry-like sand is directly poured into the sand accumulation box from the trolley via a sand supply pipe, the sand accumulation box has a substantially rectangular parallelepiped shape, so that a rectangular parallelepiped sand layer can be forcibly formed. Furthermore, if slurry-like sand is fed into this sand accumulation box by a pump, slurry-like sand can be deposited efficiently without having to wait for the sand to settle,
Further, in such a substantially rectangular parallelepiped sand accumulation box, both sides on the upper surface side are opened from the height corresponding to the thickness of the sand layer to be formed, and a hollow supply box body into which slurry-like sand is poured is provided. A hollow discharge box that discharges water, air, fine sand, and excess sand onto the trolley from the periphery of the opening on the side of the other side to the outside from the periphery of the opening on the other side The slurry-like sand is formed on both sides of the upper side of the sand accumulation box by partitioning the lower side of the interior into a plurality at predetermined intervals in the width direction perpendicular to the longitudinal direction. Since the flow from the supply box to the discharge box flows almost in parallel with the bottom of the sea, the slurry-like sand is supplied from the thin sand supply pipe through the supply box into the wide sand accumulation box. Since the flow is gentle in the sand accumulation box, Sand with a large particle size can be deposited very easily in a flow that is substantially parallel to the sand, and the sand supply pipe that feeds the slurry-like sand into the sand accumulation box is partitioned by a partition. If it branches into each section at a ratio approximately proportional to its cross-sectional area, the supplied slurry-like sand will not be unevenly deposited in the sand accumulation box,
In addition, if a support member is erected on the sand accumulation box and the upper end of the carriage protrudes from a groove formed parallel to the traveling direction, the sand accumulation box is raised after the sand layer is formed. Then, the sand accumulation box can be lowered so that it overlaps with a part of the thin layer of sand that has been formed, so that slurry-like sand can be deposited sequentially, so that a layer of sand can be formed easily and efficiently on the vast sea floor. Can be
Further, in the thin layer sanding method, the density of the slurry-like sand supplied through the sand supply pipe and the density of the slurry-like sand discharged through the discharge pipe are measured by a gamma ray densitometer to obtain substantially the same density. If the supply of the slurry-like sand is stopped at this time, it can be easily confirmed that the slurry-like sand has sufficiently accumulated in the sand accumulation box, and the sand layer of the desired thickness is more reliably contained in the sand accumulation box. As a result, the present invention has been completed.

That is, the present invention
A thin layer sanding device for forming a continuous thin layer of sand on a water permeable sheet or film laid on the bottom of the sea by a laying device installed on the tip side of the trolley. A hollow supply box that is formed in a substantially rectangular parallelepiped shape and is open from the height corresponding to the thickness of the sand layer formed on both sides perpendicular to the longitudinal direction to the upper surface, and is supplied with slurry-like sand A hollow discharge box that discharges water, air, fine sand and excess sand onto the trolley from the peripheral edge of the opening on one side to the outside of the opening on the other side. Hollow discharge boxes for discharging water, air, fine sand, and excess sand onto the trolley from the periphery to the outside are provided so as to protrude from the bottom of the rectangular parallelepiped in parallel with the longitudinal direction. To a position slightly higher than the lower end of each opening The inside is divided into a plurality of partitions at predetermined intervals in the width direction perpendicular to the longitudinal direction by a partition, and sand is filled in a state where the bottom four rounds are bottomed on a water-permeable sheet or water-permeable film laid on the bottom of the sea. Each of the compartments is branched to a position in the supply box corresponding to each of the compartments on the lower side inside the sand accumulation box in which the slurry-like sand supplied by the pump from the top of the trolley is partitioned by a partition. Water, air, fine sand in the sand accumulation box and a sand supply pipe that is supplied at a rate approximately proportional to the cross-sectional area of the sand, and a discharge opening that opens at a predetermined interval in the width direction of the sand accumulation box to the discharge box. A discharge pipe that discharges surplus sand onto the trolley, and a support member that is erected on the sand accumulation box and that protrudes from the groove formed in the trolley in parallel to its traveling direction. Thin-layer sand glazing characterized by being constructed And,
Thin layer sanding for forming a continuous thin layer of sand on the water permeable sheet or film while laying the water permeable sheet or film on the bottom of the sea by a laying device installed on the tip side of the trolley The method has a substantially rectangular parallelepiped shape with an open bottom surface, and the top surface is opened from the height corresponding to the thickness of the sand layer formed on both sides perpendicular to the longitudinal direction, and slurry-like sand is supplied. A hollow supply box that discharges water, air, fine sand and surplus sand onto the trolley from the peripheral edge of the opening of the one side to the outside. Hollow discharge boxes for discharging water, air, fine sand and surplus sand onto the trolley are projected from the periphery of the opening on the other side to the outside, and are parallel to the longitudinal direction. From the part located on the lower surface of the approximately rectangular parallelepiped, from the lower end of each opening A water-permeable sheet laid on the bottom of the sea around the bottom four corners of a sand accumulation box that is divided into a plurality of predetermined intervals in the width direction perpendicular to the longitudinal direction with a partition having a height to a slightly higher position. Or, it is grounded on a water-permeable film, and the slurry-like sand is branched from the trolley by a pump to a position corresponding to each section in the supply box partitioned by a partition through a sand supply pipe, and crosses each section. The sand is accumulated in the sand accumulation box by supplying it at a rate approximately proportional to the area, and water, air, fine sand and excess sand in the sand accumulation box are placed in the discharge box in the width direction of the sand accumulation box. A gamma ray densitometer is used to determine the concentration of the slurry-like sand to be supplied and the slurry-like sand to be discharged through a discharge body that is branched and attached to a discharge opening that opens at a predetermined interval. Measured by approximately the same The supply of the slurry-like sand is stopped when the time is reached, and the sand is passed through the support member standing on the sand accumulation box protruding from the groove formed in the carriage in parallel with the traveling direction. The sand accumulation box in which the thin layer is formed is raised, moved along the groove, the sand accumulation box is lowered so as to overlap with a part of the thin layer of sand formed, and the above operation is repeated to perform continuous thinning. After forming the layer and the support member reaches the vicinity of the end of the trolley groove in the traveling direction of the trolley, the moored trolley is moved and moored, and the support member is moved along the ridge. A thin layer sanding method characterized in that the sanding operation is repeated in the direction opposite to the traveling direction of the above and the above sanding operation is repeated.

  Further, in the thin layer sanding apparatus and the thin layer sanding method according to the present invention, the flexible tube-shaped end pressing member into which the compressed fluid is injected from the trolley is disposed on both side plates parallel to the longitudinal direction of the sand accumulation box. Since the slurry-like sand injected into the sand accumulation box is less likely to flow out from the side of the lower side of the sand accumulation box if it is provided over the entire length of the sand accumulation box in the lower part of the outer surface of the sand accumulation box. It is preferable because a sand layer can be formed efficiently.

  Further, in the thin layer sanding method according to the present invention, a plurality of grooves parallel to the traveling direction are provided on the carriage, and a sand accumulation box is provided in a state in which the upper end portion of the support member is protruded in each groove. If sand is filled in each sand accumulation box, sanding work can be efficiently performed, and in the case of using a plurality of sand accumulation boxes in this way, each sand supply body is connected to one pump via a switching unit. After the sand is filled in one sand accumulation box, the sand supply body for injecting the slurry-like sand is switched by the switching unit, and the sand is sequentially filled in the other sand accumulation boxes, and the filling is finished. It is preferable to move the sand accumulation box sequentially to the next sanding position, so that the sanding work can be done continuously and the working time can be greatly shortened. On both sides in the longitudinal direction of the water-permeable sheet or film If a water-permeable sheet or a water-permeable film is laid while wearing, it is preferable because it can prevent the water-permeable sheet or water-permeable film from being lifted, so that sanding work is easy. If the injection is started at a low flow rate and then increased to a predetermined flow rate, the slurry-like sand injected into the sand supply body is allowed to flow directly into the discharge body at the start of the injection of the slurry-like sand. This can be prevented, and the accumulation of the slurry-like sand in the sand supply body can be promoted, which is preferable.

In the thin layer sanding device and the thin layer sanding method according to the present invention, a substantially rectangular parallelepiped having a lower surface opened on a water permeable sheet or water permeable film laid on the sea bottom by a laying device installed on the tip side of the trolley. The sand accumulation box is grounded and slurry-like sand is directly injected into the sand accumulation box from the trolley via the sand supply pipe. A rectangular parallelepiped sand layer can be formed, and the slurry-like sand is pumped into the sand accumulation box by a pump, so that the slurry-like sand is efficiently deposited without waiting for the sand to settle. It is possible,
Further, in such a substantially rectangular parallelepiped sand accumulation box, both sides on the upper surface side are opened from the height corresponding to the thickness of the sand layer to be formed, and for hollow supply into which slurry sand is injected. A hollow discharge box that discharges water, air, fine sand and surplus sand onto the trolley from the peripheral edge of the opening on one side to the outside, and the opening on the other side The slurry-like sand is located above the sand accumulation box because the inner lower side is divided into a plurality at predetermined intervals in the width direction perpendicular to the longitudinal direction by partitioning. Flows from the supply box formed on both sides of the side toward the discharge box substantially parallel to the bottom of the sea, and is further supplied from the thin sand supply pipe into the large sand accumulation box through the supply box. Therefore, the flow is gentle in the sand accumulation box. Sand that has a large particle size can be deposited very easily in a flow substantially parallel to the bottom, and the sand supply pipe that feeds the slurry-like sand to the sand accumulation box is separated by a partition. Since each branch in the box is branched at a rate approximately proportional to its cross-sectional area, the supplied slurry-like sand does not deposit unevenly in the sand accumulation box,
Also, the sand accumulation box in which a thin layer of sand is formed is lifted through a support member erected on the sand accumulation box protruding from the groove formed parallel to the traveling direction on the carriage, and the groove is The sand deposit box is lowered so that it overlaps with a part of the thin sand layer formed by moving along the sand, and the slurry-like sand is sequentially deposited, so that the sand layer can be easily and efficiently deposited on the vast sea floor. Can be formed,
Further, in the thin layer sanding method, the density of the slurry-like sand supplied through the sand supply pipe and the density of the slurry-like sand discharged through the discharge pipe are measured by a gamma ray densitometer to obtain substantially the same density. Since the supply of the slurry-like sand is stopped at this time, it can be easily confirmed that the slurry-like sand has sufficiently accumulated in the sand accumulation box, and the sand layer of the desired thickness is more reliably contained in the sand accumulation box. Can be formed.

  Further, in the thin layer sanding apparatus and the thin layer sanding method according to the present invention, both side plates in which a flexible tubular end presser into which a compressed fluid is injected from a trolley are parallel to the longitudinal direction of the sand accumulation box When the sand deposit box is provided over the entire length in the longitudinal direction of the sand accumulation box, the slurry-like sand injected into the sand accumulation box is unlikely to flow out from the lower side of the accumulation box. Therefore, the sand layer can be formed efficiently.

  Further, in the thin layer sanding method according to the present invention, a plurality of grooves parallel to the traveling direction of the carriage are provided in the carriage, and a sand accumulation box is provided in a state in which the upper end portion of the support member is protruded in each carriage. When sand is filled in each sand accumulation box, sanding work can be efficiently performed. When using a plurality of sand accumulation boxes as described above, each sand supply pipe is connected via a switching unit. Connected to two pumps, and after the sand is filled in one sand accumulation box, the sand supply pipe for supplying the slurry-like sand is switched by the switching unit to sequentially fill the other sand accumulation boxes with the sand, When the sand accumulation box after filling is moved sequentially to the next sanding position, sanding work can be performed continuously, and the work time can be greatly shortened. On the both sides in the longitudinal direction of the water-permeable sheet or film When laying a water-permeable sheet or water-permeable film while wearing it, it is easy to spread sand because it can prevent the water-permeable sheet or water-permeable film from lifting, and when supplying slurry sand to the sand supply pipe When the injection is started at a low flow rate and then increased to a predetermined flow rate, the slurry-like sand injected into the sand supply body at the start of the injection of the slurry-like sand is directly converted into the discharge body. It is possible to promote the accumulation of slurry-like sand in the sand supply body by preventing the sand from flowing away.

Hereinafter, a thin layer sanding apparatus and a thin layer sanding method according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is an explanatory perspective view showing a state in which a thin layer sanding apparatus according to the present invention is mounted on a trolley, and FIG. 2 is a diagram illustrating a sand accumulation box of the thin layer sanding apparatus according to the present invention laid on the sea bottom. FIG. 3 is a perspective explanatory view showing a state where the water-permeable sheet or the water-permeable film is attached to the bottom, FIG. It is perspective explanatory drawing which shows a mode that it mounts | wears.

In the drawings, X is a trolley, and as shown in FIG. 1, the trolley X is equipped with a thin layer sanding device, and even if it is integrated with another ship loaded with slurry-like sand. Good. Y is a water permeable sheet or water permeable film Z laying device installed on the tip side of the trolley X, and may be provided in one trolley X as shown in FIG.
Furthermore, P is a pump installed on the carrier ship X. By this pump P, slurry-like sand is supplied from the carrier ship X into a sand accumulation box 1 described later. Further, R is a groove formed in the carriage X in parallel with the traveling direction, and an upper end portion of a support member 4 erected on a sand accumulation box 1 described later protrudes from the groove R.

1 has a substantially rectangular parallelepiped shape with an open bottom surface, and opens from the height corresponding to the thickness of the sand layer formed on both sides perpendicular to the longitudinal direction to the top surface, and slurry-like sand is supplied. A hollow discharge box 1b that discharges water, air, fine sand and surplus sand onto the carriage X from the peripheral edge of the opening on one side to the outside, and the hollow supply box 1a. Are protruded outward from the periphery of the opening of the other side, and are parallel to the longitudinal direction and located at a position on the lower surface of the substantially rectangular parallelepiped to a position slightly higher than the lower end of each opening. A state in which the lower end is rounded on a water-permeable sheet or a water-permeable film Z laid on the sea bottom by dividing the interior lower side into a plurality at predetermined intervals in the width direction perpendicular to the longitudinal direction by a partition 1c having It is a sand accumulation box filled with sand.
Since the sand accumulation box 1 has a substantially rectangular parallelepiped shape, a rectangular parallelepiped sand layer can be forcibly formed. Further, if slurry sand is fed into the sand accumulation box 1 by the pump P, the sand accumulation It is possible to efficiently deposit slurry-like sand without waiting for settling or the like, and the bottom surface of the sand accumulation box 1 is open, and after the slurry-like sand is deposited in the sand accumulation box 1, the sand is accumulated. It can be easily removed simply by lifting the accumulation box 1 upward.

2 divides the slurry-like sand supplied by the pump P from the top of the carriage X to a position in the supply box 1a corresponding to each lower section inside the sand accumulation box 1 partitioned by the partition 1c. This is a sand supply pipe that is supplied in proportion to the cross-sectional area of each section. Since the slurry-like sand is supplied from the thin sand supply pipe 2 to the inside of the wide sand accumulation box 1 through the supply box 1a, the sand flows slowly in the sand accumulation box 1. Sand having a large particle size can be easily deposited in a substantially parallel flow. Further, the sand supply pipe 2 for feeding the slurry-like sand into the sand accumulation box 1 branches to each section in the sand accumulation box 1 partitioned by the partition 1c at a ratio approximately proportional to the cross-sectional area thereof. The supplied slurry-like sand does not deposit unevenly in the sand accumulation box 1.
Further, when the slurry-like sand is supplied to the sand supply pipe 2, the injection is started at a low flow rate, and then the injection is performed by increasing the flow rate to a predetermined flow rate. The slurry-like sand injected into the sand can be prevented from flowing as it is to the discharge body 3 described later, and the accumulation of the slurry-like sand in the sand supply body 1 can be promoted.

3 discharges water, air, fine sand and surplus sand in the sand accumulation box 1 onto the trolley X from a discharge port opened at a predetermined interval in the width direction of the sand accumulation box 1 to the discharge box 1b. This is a discharge pipe.
The discharge pipe 3 may be branched in the same manner as the sand supply pipe 2, but like the sand supply pipe 2, slurry-like sand is dispersed in each section in the sand accumulation box 1 partitioned by the partition 1c. Therefore, it is not always necessary to branch the sand accumulation box 1 corresponding to each section in the sand accumulation box 1 like the sand supply pipe 2. Therefore, in order to increase the discharge efficiency, for example, as shown in FIG. 2, the discharge pipe 3 may be branched more than the sand supply pipe 2 or may be branched as many as or less than the sand supply pipe 2 depending on circumstances.

Reference numeral 4 denotes a support member that is erected on the sand accumulation box 1 and whose upper end protrudes from a groove R formed in the carriage X in parallel with its traveling direction.
The sand accumulation box 1 formed with a thin layer of sand is lifted through the support member 4 and moved along the groove R so as to overlap a part of the thin layer of sand formed. Is lowered and the sanding operation is repeated, and after the support member 4 reaches the vicinity of the end of the carriage X in the groove R of the carriage X, the moored carriage X is moved again. If moored and the support member 4 is returned along the groove R to the side opposite to the traveling direction of the carriage X, the sanding operation can be repeatedly and efficiently performed.

Reference numeral 5 denotes a flexible tube-shaped end presser into which a compressed fluid is injected from the top of the carriage X. This end presser 5 is provided at the lower part of the outer surface of both side plates parallel to the longitudinal direction of the sand accumulation box 1. The sand accumulation box 1 is provided over substantially the entire length in the longitudinal direction.
If the end presser 5 is provided, the slurry-like sand injected into the sand accumulation box 1 is unlikely to flow out from the lower side of the sand accumulation box 1, so that a sand layer is efficiently formed. Can be made.

Reference numeral 6 denotes a gamma ray density meter for measuring the concentration of the supplied slurry-like sand and the discharged slurry-like sand.
In the thin layer sanding method, the gamma ray density meter 6 is used to measure the concentration of the slurry-like sand supplied through the sand supply pipe 2 and the slurry-like sand discharged through the discharge pipe 3. If the supply of the slurry-like sand is stopped when the density becomes substantially the same, it can be easily confirmed that the slurry-like sand has sufficiently accumulated in the sand accumulation box 1, and the sand accumulation box can be more reliably confirmed. A sand layer having a desired thickness can be formed in 1.

  Reference numeral 7 denotes a switching unit. When a plurality of sand accumulation boxes 1 are used, if the sand supply body 2 provided in each sand accumulation box 1 is connected to one pump P via the switching unit 7. Sand pumping work can be efficiently performed with one pump P.

  8 is a belt-like load body filled with sand on the carriage X, and the water-permeable sheet or water-permeable film Z is mounted while the load body 8 is attached to both sides in the longitudinal direction of the water-permeable sheet or water-permeable film Z. If it is laid on the bottom of the sea, the water-permeable sheet or water-permeable film Z can be prevented from being lifted, and the sanding operation is easy.

In order to actually carry out thin layer sanding using the thin layer sanding device according to the present invention, first, a laying device Y for sequentially feeding roll-shaped water-permeable sheets or water-permeable films Z as shown in FIG. A trolley X in which a laying device Y is installed on the distal end side to feed a roll-shaped water-permeable sheet or water-permeable film Z as shown in FIG. Prepare. In addition, this carrier X is integrated with another ship for storing slurry-like sand to be supplied to the sand accumulation box 1 and for storing water, air, fine sand and surplus sand discharged from the sand accumulation box 1. It may consist of.
Next, the upper end portion of the support member 4 erected on the sand accumulation box 1 having a substantially rectangular parallelepiped shape whose bottom surface is opened is projected from the groove R formed in the carriage X in parallel with the traveling direction thereof. .

  In the embodiment shown in FIG. 1, two laying devices Y are installed on the tip side of the trolley X, and behind the laying devices Y are two strips parallel to the traveling direction of the trolley X. Each of the grooves R is provided with a sand accumulation box 1 in a state where the upper end portion of the support member 4 protrudes. The sand supply pipes 2 connected to the sand accumulation boxes 1 are connected to one pump P via the switching unit 7. In the embodiment shown in FIG. 1, each sand supply pipe 2 includes a branched metal part connected to the sand accumulation box 1 and a soft pipe connected to the pump P via the switching unit 7. It is configured.

Each sand accumulation box 1 is divided into three sections at predetermined intervals in the width direction perpendicular to the longitudinal direction by two partitions 1c as shown in FIG. 2, for example. The sand supply pipe 2 is also branched into three and connected to the supply box 1a of the sand accumulation box 1.
On the other hand, the discharge pipe 3 for discharging water, air, fine sand and surplus sand in the sand accumulation box 1 onto the carriage X may be branched to improve the discharge efficiency, but the sand supply pipe 2 is not necessarily used. Thus, it is not necessary to branch in correspondence with each section in the sand accumulation box 1 partitioned by the partition 1c.

Slurry sand supplied by the pump P from the top of the carriage X passes through the sand supply pipe 2 and is sent to the supply box 1a of the sand accumulation box 1. Since the supply box 1a is hollow, the slurry-like sand is supplied to the supply box 1a because it flows into the space defined by the partition 1c in the sand accumulation box 1 after being supplied to the supply box 1a. Thus, the slurry-like sand does not reach the bottom of the sea directly, and the already accumulated slurry-like sand is not rolled up or swept away.
Further, since the thin sand supply pipe 2 is supplied to the inside of the wide sand accumulation box 1 through the supply box 1a, the flow is gentle and supplied in the space partitioned by the partition 1c in the sand accumulation box 1. The slurry-like sand flows from the supply box 1a formed on both sides of the upper side of the sand accumulation box 1 toward the discharge box 1b substantially parallel to the sea bottom. In this way, a gentle flow substantially parallel to the bottom of the sea is formed in the sand accumulation box 1, so that sand having a large particle size is likely to settle, and unnecessary fine sand is swept away and discharged. Thereafter, when a sufficient amount of sand is accumulated in the sand accumulation box 1, the supplied slurry-like sand flows as it is to the discharge pipe 3, and thus the slurry-like sand in the supplied sand supply pipe 2. And the density of the slurry-like sand in the discharge pipe 3 to be discharged are measured with a gamma ray densitometer 6, and if the supply of the slurry-like sand is stopped when the density becomes substantially the same, the confirmation A sand layer having a desired thickness can be reliably formed on a difficult sea bottom.
In order to prevent the slurry-like sand from leaking from the side of the sand accumulation box 1, a flexible tube-like end presser into which the compressed fluid is injected from the top of the carrier X as shown in FIG. 5 is preferably provided over the substantially entire length in the longitudinal direction of the sand accumulation box 1 at the lower part of the outer surface of the side plates parallel to the longitudinal direction of the sand accumulation box 1.

Further, when two thin layer sanding devices are used as shown in FIG. 1, a sand layer of a desired thickness is formed in one sand accumulation box 1, and then slurry-like sand is formed by the switching unit 7. The supplied sand supply pipe 2 is switched to supply slurry-like sand into the other sand accumulation box 1, and the upper end portion of the support member 4 erected in one sand accumulation box 1 is placed on the carriage X in the meantime. It is lifted upward by gripping, etc., and moved downward in the traveling direction of the carriage X so as to overlap with a part of the formed thin layer of sand.
Then, after a sand layer having a desired thickness is formed in the other sand accumulation box 1, the process of supplying the slurry-like sand to the one sand accumulation box 1 by the switching unit 7 is repeated. A thin layer of sand can be made well.

  The above process was repeated, and the upper end of the support member 4 erected on the sand accumulation box 1 reached the vicinity of the end in the traveling direction of the carriage X of the groove R of the carriage X, and was moored. The carriage X is moved, moored again, the support member 4 is returned along the groove R to the side opposite to the traveling direction of the carriage X, and the above sanding operation is repeated, so that it continues continuously over a long distance. It is possible to work on sand.

It is an isometric view explanatory drawing which shows a mode that the thin layer sanding apparatus which concerns on this invention is equipped with the trolley. It is a perspective explanatory view which shows a mode that the sand accumulation box of the thin layer sanding apparatus which concerns on this invention was made to land on the water-permeable sheet or water-permeable film laid by the sea bottom. It is perspective explanatory drawing which shows a mode that the strip | belt-shaped load body with which sand was filled on the trolley | bogie is attached to the both sides of the longitudinal direction of a water-permeable sheet or a water-permeable film.

Explanation of symbols

1 Sand accumulation box
1a Supply box
1b Discharge box
1c Partition 2 Sand supply pipe 3 Ejector 4 Support member 5 End pressing 6 Gamma ray density meter 7 Switching part 8 Load body X Carrier Y Laying device Z Water permeable sheet or water permeable film P Pump R Strip

Claims (8)

Thin layer sand for forming a continuous thin layer of water on the water permeable sheet or film (Z) laid on the sea floor by the laying device (Y) installed on the tip side of the trolley (X) A whispering device,
A hollow supply in which slurry-like sand is supplied, which is formed in a substantially rectangular parallelepiped shape with an open bottom surface and is open from the height corresponding to the thickness of the sand layer formed on both sides perpendicular to the longitudinal direction to the top surface. Hollow discharge box (1a) for discharging water, air, fine sand and surplus sand onto the carrier (X) from the peripheral edge of the opening on one side to the outside. The body (1b) protrudes outward from the peripheral edge of the opening on the other side, and is slightly parallel to the longitudinal direction and located on the lower surface of the rectangular parallelepiped slightly from the lower end of each opening. The water permeable sheet or the water permeable film laid on the bottom of the sea, with a partition (1c) having a height up to a high position partitioned into a plurality of predetermined intervals in the width direction perpendicular to the longitudinal direction. Z) a sand accumulation box (1) in which sand is filled with the bottom four rounds bottomed,
The supply box corresponding to each of the lower compartments inside the sand accumulation box (1) in which the slurry-like sand supplied from the top of the carriage (X) by the pump (P) is partitioned by the partition (1c) A sand supply pipe (2) that branches to a position in (1a) and supplies it at a rate approximately proportional to the cross-sectional area of each section;
Water, air, fine sand, and excess sand in the sand accumulation box (1) are discharged from the discharge port opened at predetermined intervals in the width direction of the sand accumulation box (1) to the discharge box (1b). A discharge pipe (3) for discharging onto the trolley (X);
From a support member (4) which stands on the sand accumulation box (1) and whose upper end protrudes from a groove (R) formed in the carriage (X) in parallel with its traveling direction. A thin layer sanding device characterized in that it is configured.   A flexible tube-shaped end presser (5) into which compressed fluid is injected from the top of the carrier (X) is deposited on the lower part of the outer surface of both side plates parallel to the longitudinal direction of the sand accumulation box (1). 2. The thin layer sanding apparatus according to claim 1, which is provided over substantially the entire length of the box (1) in the longitudinal direction. Continuously on the water permeable sheet or water permeable film (Z) while laying the water permeable sheet or water permeable film (Z) on the sea floor by the laying device (Y) installed on the tip side of the trolley (X) A thin layer sanding method for forming a thin layer of sand,
A hollow supply in which slurry-like sand is supplied, which is formed in a substantially rectangular parallelepiped shape with an open bottom surface and is open from the height corresponding to the thickness of the sand layer formed on both sides perpendicular to the longitudinal direction to the top surface. Hollow discharge box (1a) for discharging water, air, fine sand and surplus sand onto the carrier (X) from the peripheral edge of the opening on one side to the outside. The body (1b) protrudes outward from the peripheral edge of the opening on the other side, and is slightly parallel to the longitudinal direction and located on the lower surface of the rectangular parallelepiped slightly from the lower end of each opening. The lower end of the sand accumulation box (1) is laid on the bottom of the sea by a partition (1c) having a height up to a high position. The water-permeable sheet or the water-permeable film (Z)
Corresponding to each section in the supply box (1a) in which the slurry-like sand is partitioned by the partition (1c) through the sand supply pipe (2) by the pump (P) from the top of the carriage (X) The sand is deposited in the sand accumulation box (1) by being branched to a position and fed at a rate approximately proportional to the cross-sectional area of each section;
Water, air, fine sand and surplus sand in the sand accumulation box (1) are discharged into the discharge box (1b) at a discharge opening opened at a predetermined interval in the width direction of the sand accumulation box (1). It is discharged onto the trolley (X) through the discharge body (3) that is installed in a branch,
When the concentration of the slurry-like sand to be supplied and the slurry-like sand to be discharged is measured by a gamma ray densitometer (6) and the density becomes substantially the same, the supply of the slurry-like sand is stopped,
A thin layer of sand via a support member (4) erected on the sand accumulation box (1) protruding from a groove (R) formed in the carriage (X) in parallel with its traveling direction. The sand accumulation box (1) in which the sand is formed is moved up and moved along the groove (R), and the sand accumulation box (1) is lowered so as to overlap a part of the thin layer of sand formed. The above operation is repeated to form a continuous thin layer,
After the support member (4) reaches the vicinity of the end of the carriage (X) in the groove (R) of the carriage (X), the moored ship (X) is moved. A thin layer sanding method characterized by mooring, returning the support member (4) along the groove (R) to the opposite side of the traveling direction of the carriage (X) and repeating the sanding operation.   After the bottom surface of the sand accumulation box (1) opened on the water-permeable sheet or film (Z) laid on the sea bottom by the laying device (Y), the longitudinal direction of the sand accumulation box (1) Is injected into the flexible tube-shaped end presser (5) provided on the lower part of the outer surface of both side plates parallel to the base plate (X) from the top of the carriage (X). The sand accumulation box (in such a manner that no gap is formed between the water permeable sheet or the water permeable film (Z) laid on the surface and the lower portions of both side surfaces of the sand accumulation box (1) that is grounded) The thin layer sanding method according to claim 3, wherein 1) is filled with sand.   A state in which a plurality of grooves (R,...) Are provided in the carriage (X) in parallel with the traveling direction of the carriage (X), and the upper end portion of the support member (4) is projected in each groove (R). 5. A thin layer sanding method according to claim 3 or 4, wherein a sand accumulation box (1) is disposed in each of the sand accumulation boxes (1).   Each sand supply pipe (2) is connected to one pump (P) via a switching unit (7), and after the sand is filled in one sand accumulation box (1), the slurry is switched by the switching unit (7). The sand supply pipe (2) that supplies the sand is switched to fill the other sand accumulation boxes (1) sequentially with sand, and the sand accumulation box (1) that has been filled is next sanded. The thin-layer sanding method according to claim 5, which is sequentially moved to each other.   The water-permeable sheet or the water-permeable film (8) is mounted on both sides in the longitudinal direction of the water-permeable sheet or water-permeable film (Z) through the belt-shaped load body (8) filled with sand on the carrier (X). The thin layer sanding method according to any one of claims 3 to 6, wherein Z) is laid.   8. The method according to claim 3, wherein when the slurry-like sand is supplied to the sand supply pipe (2), the injection is started at a low flow rate, and then the slurry-like sand is injected at a predetermined flow rate. The thin layer sanding method described in 1.

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