JP5421871B2 - Sludge confinement method, bottom layer constraining member and gabion for bottom layer confinement used therefor - Google Patents

Description

  The present invention relates to a sludge containment method for creating a shallow field in the upper layer of the bottom layer in sea areas, lakes, rivers, canals, and the like, and a bottom layer restraint member and a bottom layer restraint gabion used therefor, in addition, as a bottom layer restraint member, It effectively utilizes shells that are currently disposed of as industrial waste.

  In recent years, social needs for improvement of the water environment such as sea areas, lakes, rivers, canals, etc. have increased, and the creation of shallow fields has attracted attention as an effective means for realizing this. In addition, the creation of a new shallow area at the bottom of the water requires the use of natural materials as a consideration for the environment, and more preferably the use of natural materials that are currently disposed of as industrial waste. ing.

Examples of conventional techniques for shallow-field construction include, for example, constructing a submerged dike that divides a certain area of the seabed and sprinkling sand material inside the demarcated area, or utilizing industrial waste for the same purpose There are those using blast furnace slag generated in the steel manufacturing process (see, for example, Patent Documents 1 and 2 below).
Japanese Patent No. 3143776 JP 2005-240543 A

  The creation of such a shallow field has the problem of being carried out at low cost and high efficiency, but the problem here is the disposal of sludge deposited in the bottom layer of the water area that creates the shallow field.

  Conventionally, this sludge treatment has been carried out by 1) a method for removing sludge with a scissors, and 2) a method for containing sludge by sand covering means for laying sand or the like on the upper layer of the sludge. Therefore, none of them can be effective solutions.

  With regard to 1), a large area is required for processing, disposal, and dumping of the removed sludge on land, and the cost required for treating organic substances contained in sludge is enormous. In 2), the sand 2 laid for creating the shallow field is generally buried in the sludge layer 1 having a very low strength, and the sand covering effect is not sufficiently exhibited. FIG. 9 shows such a state. Even if the crushed stone 3 serving as a submerged dike for restraining the sand to be laid from the surroundings is inserted, it is buried in the sludge and does not function as a submerged dike.

  The object of the present invention is to solve the disadvantages of the prior art described above, and in sea areas, lakes, rivers, canals, etc., when constructing a shallow field as an upper layer of the bottom layer, the workability is simple and the strength properties of the bottom layer such as sludge. A sludge containment method that can be used effectively for shells that are currently disposed of as industrial waste, while being able to stably obtain a space suitable for the growth of living organisms that is less susceptible to the adverse effects of An object of the present invention is to provide a water bottom layer constraining member and a water bottom layer constraining gabion for storing the water bottom layer constraining member.

  In order to achieve the above-mentioned object, the present invention is a sludge containment method in which dish-shaped shells such as bivalves inserted through a linear member are arranged substantially parallel to each other in the longitudinal direction of the linear member. The bottom layer constraining members formed by linking them together are placed inside the bottom layer constraining gabion so that the peripheral positions of the shells overlap each other with a gap between them, and this bottom layer constraining gabion is placed in the upper layer of the bottom layer. A plurality of horizontally installed gabions for water bottom layer restraint are installed in a plurality of horizontal directions on the bottom layer of the water bottom layer and stacked in a plurality of stages in the depth direction. The gist of the present invention is that the linear member into which the water bottom layer constraining member is inserted is installed at the bottom of the water so that the longitudinal direction thereof is substantially orthogonal.

  As the bottom layer constraining member used in the sludge containment method, a hole is made in the substantially central part of a dish-like shell such as a bivalve shell, the linear member is inserted through the hole provided in the shell, and the length of the linear member is long. The movement of the shells in the direction is restricted, and a locking member that holds the gap between the shells is provided on the linear member between the shells. That the shell inserted through the linear member is a scallop, or is a oyster, abalone, the locking member provided on the linear member has a cross-section with a hole through which the linear member passes in the center. Or a cross-sectional C-shape having a hole through which the linear member penetrates at the center and a cut portion into which the linear member is fitted on the side surface, and the linear member It is made of an elastic member that closes the notch when fitted into the Is for summarized as providing a wheel differential linear member itself.

  As a waterbed layer constraining gabion used for sludge containment, a dish-shaped shell such as a bivalve inserted through a linear member is arranged in parallel with a distance in the longitudinal direction of the linear member. The bottom layer constraining member formed by linking the beads together is stored inside the bottom layer constraining gabion with the peripheral positions of the shells overlapping each other with a space between them, and both ends of the linear member are confined to the bottom layer constraining gabion. The gist is to bond to the opposing surface portions of the.

  The water bottom layer constraining member according to the present invention is formed by arranging dish-shaped shells such as bivalves inserted through the linear member in parallel in the longitudinal direction of the linear member and connecting them in a rosary manner. Yes, the bottom layer constraining member is placed inside the bottom layer constraining gabion so that the peripheral positions of the shells overlap each other, so that the void area existing between the shells is limited, so that sludge can be restrained reliably. it can. The sludge accumulated in the lower layer of the shallow water formation area is generally extremely low in strength, so the bottom-bed confining gabions sink to some extent in the sludge layer, but in normal cases, into the sludge layer of the bottom-floor confining gabions The maximum burial depth remains at the depth of one layer of the waterbed confining gabion or less. The underwater layer constraining gabion itself is lightweight, and the specific gravity of the shell installed inside is approximately 1.5 or less, so that it effectively works to prevent burial. For laying on the bottom of the water, it is preferable to connect a plurality of water bottom layer constraining gabions in advance in a plane and lay them on the bottom of the water in order to efficiently perform the hanging work with a crane. In order to lay on a wider range of water bottoms, water bottom layer constraining gabions installed on the water bottom by divers or the like may be connected to each other.

  In this way, by providing a water bottom layer restraining member in the water bottom layer restraining gabion installed on the water bottom layer made of sludge, etc., water is prevented by preventing sedimentation of the water bottom layer restraining gabion into the water bottom layer such as sludge. It can be installed stably on the bottom layer, and sand materials and other materials that can be set up for shallow field construction can be enclosed in a waterbed for restraining the bottom layer to prevent movement of the set up material due to water flow. It becomes.

  As described above, the sludge containment method of the present invention and the bottom layer constraining member and the bottom layer constraining gabion used for the sludge layer are only installed directly on the bottom layer such as sludge accumulated in the water area forming a shallow field. It is possible to sew sand and other shallow ground materials on the bottom without requiring special processes such as dredging, disposal and dumping, and at present, disposal as industrial waste is required. It can effectively use shells made of natural materials whose social needs are increasing nationwide.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, the water bottom layer restraining member and the water bottom layer restraining gabion used in the sludge containment method of the present invention will be described. FIG. 1 is a side view of the water bottom layer restraining gabion of the present invention, FIG. In the figure, 4 is a housing, and 5 is a water bottom layer constraining member.

  The water-bottom layer restraining member 5 has a relatively large area, and has a hole 7 formed at a substantially central portion of an abalone shell 6 which is a bivalve or scallop such as a scallop or a oyster, which is a substantially flat plate-like or substantially flat shell. Opening, the linear member 8 is inserted into the hole 7 provided in the shell 6, the position movement of the shell 6 in the longitudinal direction of the linear member 8 is restricted, and the locking member 9 that maintains the interval between the shells 6. Were provided on the linear member 8 between the shells 6, and the shells 6 were arranged in parallel and spaced apart to form a rosary chain.

  The linear member 8 may be made of a metal such as a wire or a synthetic resin such as a nylon rope. Natural fiber strings can also be used.

  The locking member 9 is provided on the linear member 8 and is not shown in the drawing, but has a cross-section having a through-hole at the center portion. The cross-piece is formed by a pipe or ring body, or the hole through which the linear member 8 passes. Is a C-shaped cross section having a cut-out portion into which the linear member is fitted on the side surface, and an elastic member so that the cut-in portion closes when fitted into the linear member. The hose body is made of.

  When the locking member 9 is a pipe or ring having a cross-sectional shape, it may be made of metal, synthetic resin, wood, etc., but it is relatively hard, and the linear member 8 includes the shell 6 and the locking member. 9 are alternately inserted, and the locking member 9 is interposed between the shells 6, so that the movement of the position of the shells 6 in the longitudinal direction of the linear member 8 is restricted, and the interval between the shells 6 is maintained.

  When the locking member 9 is a hose body made of an elastic member, a flexible material such as synthetic resin or synthetic rubber is used. However, the linear member 8 is formed by the locking member 9 being interposed between the shells 6. It is the same in that the movement of the position of the shell 6 in the longitudinal direction of the shell 6 is restricted and the interval between the shells 6 is maintained.

  After the locking member 9 and the shell 6 are alternately inserted into the linear member 8, the locking member 9 is deformed so as to close the cut portion of the C-shaped cross section. Alternatively, the linear member 8 through which the shell 6 has been inserted in advance is passed into the later-described casing 4, and then the cut portion of the locking member 9 is fitted into the linear member and finally merged. It is also possible to create it by deforming it.

  As another embodiment, the locking member 9 can also be formed by providing a ring difference on the linear member 8 itself. The linear member 8 itself is created by making a difference between the rings, or by connecting another linear member to the linear member. In this case, it is sufficient that the locking member 9 has a size that does not pass through the hole 7 provided in the shell 6. By forming the locking member 9 before and after the shell 6, the shells 6 are restrained one by one, and the shells 6 are connected to each other. The interval is maintained by adjusting the interval between the locking members 9.

  In any of the above cases, a locking ring body 8 a can be formed at the end of the linear member 8.

  In the casing 4 serving as a water bottom layer restraining gabion, a water bottom layer restraining member 5 is housed in a state where the peripheral positions of the shells 6 are overlapped with each other at intervals, and the movement of the shells in the longitudinal direction of the linear member is prevented. It can be restrained and needs to be installed on the bottom of the water so that the shape of the housing 4 can be uniquely maintained. Therefore, it is desirable that at least each side member has a rigidity that can hold the surface surrounding it, rather than a net bag shape whose shape is deformed indefinitely. The material may be metal or synthetic resin.

  Further, in order to facilitate handling during transportation and storage, the housing 4 may be configured to be foldable. The material is not particularly limited as long as it has corrosion resistance against sulfides and salt. However, it is preferable to use polyester that has been used for fishing reefs installed in the sea and has been proven to be durable. Although the illustrated water bottom layer constraining gabion has a rectangular parallelepiped shape, the shape is not limited thereto, and may be a cube, a cylinder, a polygonal column, or the like.

  Further, a biodegradable resin composition may be used for the casing 4. In this case, the biodegradable resin composition is composed of a mixture of a biodegradable natural material and a biodegradable synthetic resin. As the biodegradable natural material, rice flour, starch, modified starch, starch derivative, cellulose, cellulose derivatives, etc. are used. For example, when rice flour is used, a fine particle size of about 1 to 100 μm is appropriate, and preferably 38 μm (400 mesh).

  Examples of biodegradable synthetic resins include aliphatic polyester, polycaprolactone, polyethylene succinate, polybutylene succinate, polylactic acid, polylactide acid, polyglycolic acid, acetylcellulose, and polyvinyl alcohol. Biodegradable synthetic resins can be used.

  When the biodegradable resin composition to be produced is 100 parts by weight, the mixing ratio of the biodegradable natural material and the biodegradable synthetic resin is biodegradable natural material: biodegradable synthetic resin = 2 to 40:98. The blending of components such as ˜60 is preferred.

  For example, in order to produce a pellet-shaped resin composition, a predetermined amount of the biodegradable synthetic resin is melt-kneaded in an extruder at a temperature equal to or higher than its melting point, and the biodegradable composition is added to the kneaded product. When a predetermined amount of a natural material (rice flour) is mixed and dispersed and mixed, and extruded from a nozzle in a string shape, it is granulated into a pellet.

  The resulting pellet-shaped resin composition can be molded into a net by injection molding, extrusion molding (for inflation and T-die molding), blow molding, sheet molding, and vacuum molding in the same manner as conventional synthetic resin pellet-shaped compositions. Is possible.

  The linear member 8 that forms the water bottom layer constraining member 5 in the housing 4 is viewed from the cross-section of the housing 4 in the horizontal direction of the plane (left and right direction in the drawing 1) and the side surface depth direction (the depth direction in the drawing 2). Both ends of the linear member 8 are connected to a surface portion constituting the housing 4.

  Further, the linear member 8 that passes through the shell is such that the adjacent shell 6 is a shell as viewed from the cross-section of the housing 4 in the horizontal direction of the plane (left and right direction in the drawing 1) and the side surface depth direction (the depth direction in the drawing 2). Are placed in the housing 4 so that their peripheral positions overlap each other at intervals.

  Since these shells 6 are fixed at predetermined positions of the linear members 8 by the locking members 9, the linear members 8 do not move in the longitudinal direction, and the bottom of the casing 4 (water bottom constraining gabion). The bottom layer such as sludge, sand, etc., which is set up in the upper layer, is securely enclosed in the gap between these shells 6, and the subsidence of the frame 4 (water bed constraining gabions) Therefore, it is possible to prevent the material such as sand from flowing out due to the water flow.

  The sludge containment method of the present invention is a method of forming a shallow body 4 in which a water bottom layer constraining member 5 is housed, that is, a water bottom layer constraining gabion is laminated in the depth direction. FIG. This is a construction example in which the submerged layer-constrained gabion is relatively shallow and is generally less than or equal to the size of the submerged layer-constrained gabion.

  First, a work boat (not shown) is made to reach a predetermined position on the water, and the water bottom layer constraining gabion according to the present invention is suspended by a crane or the like and installed on the water bottom. At this time, the sludge accumulated in the lower layer of the shallow water formation area is generally extremely low in strength, so that the bottom layer confining gabions sink to some extent in the sludge layer, but the sludge confined in the bottom layer confining gabions of the present invention. The shell 6 inserted through the passed linear member 8 has a gap area existing between the shells 6 because its peripheral position overlaps each other with an interval when viewed from the plane and side cross-sections of the water bottom layer constraining gabions. Since it is limited, sludge is surely restrained, and the submergence restraint gabions are buried in the sludge layer at a depth of at most about the depth of the bottom bottom restraint gabions or less.

  The underwater layer constraining gabion itself is lightweight, and the specific gravity of the shell installed inside is approximately 1.5 or less, so that it effectively works to prevent burial. In order to lay the bottom layer constraining gabions on the bottom of the water, it is preferable to connect a plurality of bottom layer constraining gabions in advance in a plane and lay them on the bottom of the water in order to efficiently perform the suspension work with a crane.

  In order to lay the bottom layer constraining gabions over a wider range of water bottoms, the bottom layer constraining gabions may be connected to each other by a diver or the like.

  From the upper part of the bottom layer constraining gabion that is partially buried in the sludge layer, the sand 10 as the hoisting material is dropped from the bucket 11 etc. of the crane of the work ship to the upper part of the bottom layer constraining gabion. Sand 10 is charged.

  The shell 6 inserted into the linear member 8 spanned in the water bottom layer constraining gabion has a peripheral position that overlaps with a gap when viewed from the plane and side cross sections of the water bottom layer constraining gabion. Since the gap area existing between them is limited, the sand 10 which is a freshly-sealed material is surely enclosed between the shells 6 and can be prevented from moving due to the water flow on the seabed.

  In this embodiment, the lower layer portion of the water bottom layer constraining gabion is filled with the sludge layer α, and the upper layer portion is filled with the sand 10 which is a whirling member, so that a shallow field is effectively created.

  FIG. 6 shows a construction example in the case where a water bottom layer such as a relatively deep sludge has accumulated in the shallow water formation water area for one layer or more of the water bottom layer constraining gabions. When the water bottom layer such as sludge has a certain thickness or more, even if it is the water bottom layer constraining gabion according to the present invention, there is a possibility that only one layer is buried in the sludge layer α.

  In this case, a plurality of layers of water bottom layer constraining gabions are stacked and suspended on the bottom of the sea to expose the upper water layer constraining gabions above the sludge layer α. Sand 10 is dropped from the upper part of the waterbed confining gabion to create a shallow field. In addition, the crushed stone 12 is thrown into the bottom water bottom layer constraining gabion to promote settlement.

  Even in this case, in order to improve the efficiency of the suspension work by the crane, a plurality of water bottom layer constraining gabions are connected in advance in the plane and in the height direction, and this is laid on the bottom of the water, or the bottom of the bottom In order to lay the restraining gabions, the bottom water layer restraining gabions may be connected to each other by a diver or the like. If the thickness of the sludge layer α is known in advance, a plurality of water bottom layer constraining gabions that are sufficient to be exposed based on this thickness are stacked and connected in advance, and this is laid on the water bottom layer. May be.

  In the embodiment shown in FIG. 5 and FIG. 6, each of the constituent surfaces is flat and explained based on the net-shaped water bottom layer constraining gabion, but the bottom surface shape depends on the undulation state of the water bottom surface. In consideration of the restraining effect of the bottom surface of the water or the hoisting material, it is also possible to adopt a plate-like member in which a part of the constituent surface is replaced with a net.

  FIG. 7 shows that when the surface direction of the shell 6 installed in the water bottom layer constraining gabion is only aligned in one direction, the water bottom layer such as sludge and the striking material such as sand flow out from the open direction of the surface, An example of construction when there is a problem that it cannot be sufficiently restrained or contained is shown.

  As shown in FIG. 7, the water bottom layer constraining gabion surrounds the central water bottom layer constraining gabion group A in which the surface direction of the shell 6 is aligned in one direction (vertical direction in the drawing). A bottom layer constraining gabion group B over which the linear member 8 is stretched is laid in a direction substantially orthogonal to the direction in which the linear members in the group A are crossed, and moved in the bottom layer constraining gabion group A (drawing). The bottom layer such as sludge and the upright material that can possibly be restrained and confined by the bottom layer constraining gabion group B are ensured.

  The laying pattern of the water bottom layer constraining gabions group A and B is not limited to this, and the main point is that the water bottom layer constraining facility located in the center is viewed in plan view of the water area where the water bottom layer constraining gabions are installed. It is that the water bottom layer constraining gabion group surrounding the water bottom layer such as sludge and the stroking material constrained by the water gabion group can be constrained.

  Although not shown in the drawings, by covering the bottom of the water bottom layer constraining member according to the present invention in a water bottom layer constraining gabion with sand from the top, the wealth in the dam lake which is currently a problem. It can also be used as a preventive measure against nutrition.

  When nutrient salts flow out from organic sludge (such as sludge) deposited on the bottom of a dam lake, eutrophication occurs in the lake water, and abnormal conditions such as blue sea bream occur, causing environmental deterioration. There is a means to cover the upper layer of the accumulated organic sludge. If the water bottom layer restraining member 5 according to the present invention is placed in a water bottom layer restraining gabion on the water bottom and covered with sand from the top, the above problem can be solved and the water quality of the dam lake can be improved. Can be realized.

  Furthermore, the water bottom layer constraining gabion containing the water bottom layer restraining member of the present invention is a foundation for refilling the bottom of the water dug once dug down in the creation of a shallow place due to the revetment construction in a place near sludge. It is possible to apply as FIG. 8 shows such a situation. When constructing the newly constructed revetment 14, the water bottom layer constraining gabions of the present invention are lined up in a place dug down by construction, and the temporary storage material 13 is sprinkled thereon.

It is a side view showing one embodiment of the water bottom layer restraint gabion of the present invention. It is a vertical side view which shows one Embodiment of the gabion for water bottom layer restraint of this invention. It is a perspective view which shows the manufacture process of the water bottom layer constraining member of this invention. It is a side view of the water bottom layer constraining member of the present invention. It is a side view showing one embodiment of the sludge containment method of the present invention. It is a side view which shows other embodiment of the sludge containment construction method of this invention. It is a top view which shows other embodiment of the sludge containment construction method of this invention. It is a side view which shows one of the utilization examples of the gabion for water bottom layer restraint of this invention. It is explanatory drawing that the sludge cannot be contained.

DESCRIPTION OF SYMBOLS 1 ... Sludge layer 2 ... Sand 3 ... Crushed stone 4 ... Body 5 ... Submarine layer restraint member 6 ... Shell 7 ... Hole 8 ... Linear member 8a ... Locking ring body 9 ... Locking member 10 ... Sand 11 ... Crane bucket 12 ... Crushed stone 13 ... Temporary material 14 ... New revetment

Claims (11)

  A water-bottom layer constraining member formed by linking together a dish-shaped shell such as a bivalve inserted through a linear member, arranged in parallel with a distance in the longitudinal direction of the linear member. A sludge containment method characterized in that the seashells are placed in the bottom layer constraining gabions in a state where the peripheral positions of the shells are overlapped with each other at intervals, and a plurality of the bottom layer constraining gabions are installed horizontally in the upper layer of the bottom layer. .   2. The sludge containment method according to claim 1, wherein a plurality of water bottom layer constraining gabions are installed horizontally in the upper layer of the water bottom layer and stacked in a plurality of steps in the depth direction.   The sludge containment method according to claim 1 or 2, wherein the water bottom layer constraining gabion is installed on the water bottom so that the longitudinal direction of the linear member through which the water bottom layer constraining member is inserted is substantially orthogonal.   A hole is made in the approximate center of a dish-shaped shell such as a bivalve shell, a linear member is inserted through the hole provided in the shell, and the movement of the shell in the longitudinal direction of the linear member is restricted. An underwater layer used for sludge containment method, characterized in that a locking member that holds the gap between the shells is provided on the linear member between the shells, and the shells are formed in a daisy chain by arranging them substantially parallel to each other at intervals. Restraint member.   The seabed constraining member used in the sludge containment method according to claim 4, wherein the shell inserted through the linear member is a scallop.   The water bottom layer constraining member used in the sludge containment method according to claim 4, wherein the shell inserted through the linear member is an oyster.   The water bottom layer constraining member used in the sludge containment method according to claim 4, wherein the shell inserted through the linear member is abalone.   The water bottom layer constraining member used for the sludge containment method according to claim 4, wherein the locking member provided in the linear member has a cross-sectional shape having a hole through which the linear member passes in the center.   The locking member provided in the linear member has a C-shaped cross section having a hole through which the linear member penetrates in the center, and a cut portion into which the linear member is fitted on the side surface thereof, and The water bottom layer constraining member used for the sludge containment method according to claim 4, comprising an elastic member that closes when the cut portion is fitted to the shaped member.   The water bottom layer constraining member used in the sludge containment method according to claim 4, wherein the locking member provided on the linear member is a knot that provides a ring difference on the linear member itself.   A water-bottom layer constraining member formed by linking together a dish-shaped shell such as a bivalve inserted through a linear member, arranged in parallel with a distance in the longitudinal direction of the linear member. The sludge confinement is characterized in that the peripheral position of the shell is placed in a state where the peripheral positions of the shells overlap each other inside the water bottom layer-constrained gabion, and both ends of the linear member are coupled to the opposing surface portions of the water bottom layer-constrained gabion Gabion for water layer confinement used in the construction method.

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