JP6004252B2 - Soil stripping collection method and bucket - Google Patents

Description

  The present invention relates to a method for removing a contaminated soil surface layer, and is particularly suitable for removing a contaminated soil surface layer whose surface layer is contaminated with a thin layer width of about 10 cm or less from the soil surface by heavy metals or radioactive substances. Concerning construction method.

  In recent years, heavy metals such as zinc, copper, cadmium, lead, mercury or hexavalent chromium; harmful substances such as selenium, arsenic, fluorine or boron; radioactive pollutants (hereinafter these substances are collectively referred to as “pollutants”) Contamination of the soil surface such as farmland and school ground (ground) is also a problem. For example, heavy metals released from mines, etc. contained in rivers used as irrigation water, and radioactive materials released into the atmosphere due to accidents at nuclear power plants, etc., are used for soil such as farmland, pastures, or schoolyards. It has been confirmed that it remains on the surface layer within a depth of about 5 cm from the ground surface, more specifically, within a depth of about 2 cm from the ground surface. In order to run a safe and secure agriculture, livestock farming or social life, it is desirable to remove contaminated soil quickly and reliably, and at low cost so as to minimize waste.

  Conventionally, physical methods, chemical methods, and biological methods have been adopted as methods for treating soil contaminated with pollutants.

  Examples of physical methods include soil stripping, soil removal, upside down (inversion plowing), and the like. Conventional removal devices used to remove contaminated soil by physical methods typically use self-propelled construction or agricultural machinery with tires or crawler belts. These removal devices have a front / rear end or an intermediate portion between the front wheel and the rear wheel, such as a bucket or earthing plate that can be attached or detached with the front side opened or recessed with respect to the traveling direction. It is attached. Hereinafter, a case where a working unit such as a bucket is attached to the construction machine will be described. The working unit such as a bucket is generally attached to be movable up and down by a hydraulic cylinder or the like.

  When removing the soil surface layer in the area to be removed, with a general bulldozer, loader or grader, the working part such as a bucket is moved up and down, and the edge part at the lower end is inserted into the soil surface layer. The entire surface of the traveling construction machine is moved forward or backward to separate the soil surface layer from the underlying soil and peel it off. Furthermore, the soil surface layer is removed by scooping up the soil, pushing it in the traveling direction, or extruding it in either the left or right direction. Then, the removed soil is collected by a loader or a hydraulic excavator or the like and carried out (see, for example, Patent Document 1).

  Further, when removing the soil surface layer using a hydraulic excavator, in addition to the removal by self-propelling as described above, for example, by operating the arm back and forth or up and down with a hydraulic cylinder, the bucket is slightly placed on the soil surface layer. It can be peeled off by being inserted into and moved parallel to the front side or the near side. After that, the excavator drops the soil surface layer peeled off in the bucket once onto the side of the construction machine and accumulates it, or drops it on the loading platform of the transport vehicle and accumulates it, so that the soil surface layer in the removal area Can be removed.

  Next, as a chemical method, for example, when the pollutant is cadmium, an alkaline material such as calcium silicate is added to the soil. The method of doing is mentioned. In addition, when the pollutants are mainly heavy metals such as mercury or hexavalent chromium, or harmful substances such as fluorine or boron, a solidifying agent such as a magnesia solidifying agent or cement solidifying agent is mixed into the contaminated soil. In addition, a method has been proposed in which soil is solidified (for example, solidified so as to have a predetermined uniaxial compressive strength), insolubilized, and contaminants are blocked and contained (for example, Patent Documents 2 to 6).

  Biological methods include, for example, planting cruciferous plants in the soil when the pollutant is cadmium, and absorbing, adsorbing and fixing the pollutants in the soil to the plant. Phytoremediation method and the like (for example, Patent Document 7).

JP 2006-52595 A JP 2003-225640 A JP 2003-334526 A Japanese Patent No. 3675766 Japanese Patent No. 4074857 Japanese Patent No. 4109017 JP 2007-289897 A

  However, in the physical method, when the soil is peeled off, if a commonly used heavy machine such as a bulldozer is used, a work error of about 10 cm occurs due to the operation accuracy of the heavy machine, and the heavy machine is peeled off. The amount of soil increases, construction costs may increase, and contaminated soil may be left behind, which is problematic in terms of economy and safety. In recent years, there are heavy machinery in which the operation accuracy of the front working unit is controlled by laser beams, etc., but still there is a work error of ± 2 cm to ± 3 cm, which may leave behind, and pollutants such as radioactive substances It is difficult to accurately and reliably peel off the soil surface layer within a depth of 5 cm from the remaining soil surface. When carrying out customer soil on the contaminated soil surface, new soil must be brought in from an uncontaminated area, and there is an economic problem such as increased construction costs. When performing upside down (reversal tillage), the reversal rate decreases due to soil properties and soil quality (for example, when reversing tillage with a bulldozer, the reversal is reversed with respect to 100% of the reversed soil amount) The amount of soil is about 60%), and there is a possibility that contaminants may partially remain on the surface layer, which is problematic in terms of safety. In addition, if the soil is turned upside down, the contaminated soil remains in the subsoil after construction, and the pollutants are transferred to the surface by capillarity, and the pollutants are absorbed from the roots of the plants, and the cultivated crop There is a problem that safety is not ensured.

  In recent years, in order to remove soil contaminated with only the surface layer, there is a demand to peel and remove only the soil surface layer having a depth of 2 to 3 cm from the surface of the soil. However, in the conventional method in which the working part such as a bucket attached to a self-propelled construction machine is pushed forward in the traveling direction to peel off the soil surface layer, the depth of the soil surface layer is within an error range of about 10 cm from the surface. In general, the soil surface layer was stripped thickly by taking safety measures.

  One of the reasons for this variation is that if the self-propelled construction machine is advanced in the direction of travel due to unevenness of the soil surface (undulations or irregularities, etc.), the vertical swing, forward tilt or backward tilt will occur. This is because the vertical movement and the change in the insertion angle also occur in the working part such as the above, and the depth of the working part inserted into the soil is not stable. In addition, working parts such as arms and buckets are connected to the self-propelled construction machine by pivots, and the lower end of the work such as the tip of the arm and buckets is directed from the ground to the ground or from the ground to the ground. This is because, since it rotates in an arc shape, it is difficult to adjust and set the depth at which the bucket is inserted into the soil within a small range of 10 cm or less by the operation lever.

  Another reason is that there is a reaction force against a working part such as a bucket from the self-running direction in the case of self-running, and a downward stress due to the weight and load of the working part such as a bucket. This is because, for example, when a working part such as a bucket is advanced in the traveling direction of the self-running and the soil surface layer is peeled off, the reaction force is generated due to the resistance of the soil surface layer against the force to advance in the traveling direction. Push the working part back. However, since the working part such as the bucket is inserted obliquely with respect to the soil surface layer, a force to push down the working part such as the bucket is generated as a reaction force as a component force of the reaction force. When the soil is hard, the reaction force to the working part such as the bucket increases, and the amount of variation in the depth at which the edge of the working part such as the bucket is inserted deeper than intended by the operator increases. To do. In addition, when the peeled soil surface layer is pushed into the working portion such as a bucket by self-running, a force is generated to push down the working portion such as the bucket due to the weight of the soil surface layer.

  Furthermore, when a working unit such as a bucket is attached to the tip of the traveling direction of the self-propelled construction machine and the soil surface layer is peeled off by moving in the traveling direction, the working unit such as a bucket is located between the operator and the soil surface layer of the removal area. It may be an obstacle to be visually recognized, and a ground contact portion of an edge of a working unit such as a bucket may become a blind spot of an operator. In this case, since the operator cannot visually recognize the situation where the edge of the working part such as the bucket is inserted into the soil surface layer or the depth to be peeled off, the operator performs the work in anticipation from the situation that was visible before that, In many cases, the actual situation is different, and the work error is further expanded.

  In order to suppress the increase in the amount of soil to be removed due to such fluctuations and errors, when the soil surface layer is peeled off thinly, the vertical movement of the bucket and the variation in the insertion angle still occur, so the soil surface layer Leftovers are likely to occur. Then, the work efficiency decreases due to “requires work again”, and man-hours, fuel costs, etc. increase and construction costs increase. On the other hand, if a safety measure is taken as is generally done and the soil surface layer is peeled off thickly, unintended soil below the soil surface layer is also removed. In that case, the amount of soil to be removed increases, the amount of work and the amount of conveyance increase, the number of conveyance means, the number of man-hours, the fuel cost, etc. increase, and the construction cost increases.

  In addition to self-propelled construction machines, agricultural machines and snow removal machines that have a tire or a crawler belt and are capable of similar work are known. They can be attached with working parts such as detachable blades and levelers. However, the blade is used to remove the soil surface layer by pushing the soil surface layer in the direction of travel or pushing it in either the left or right direction like the bucket. Have Further, the leveler is not used for removing or transporting the soil but for keeping the surface of the soil surface level. In the case of leaving it evenly, the problem of “requires work again” occurs as in the case of trying to remove the soil surface thinly in order to suppress the increase in the amount of soil to be removed. To do. The same applies when the blade is used as a leveler.

  Furthermore, since most of the agricultural machines are rear working machines, the soil surface layer in the area to be removed is once stripped with a tire or a crawler belt and then stripped off with a blade or the like. In this case, when it is stepped on, the soil to be removed, such as contaminated soil, diffuses from the surface layer to the lower layers, leaving behind easily and increasing the stripping thickness. In addition, since the depth at which the operator is stripped off by the rear working machine cannot be visually recognized, there is a problem that work errors are likely to occur.

  In the chemical method, chemical substances are currently added to the soil to suppress the absorption of pollutants in agricultural crops, or solidifying agents are added and mixed in the soil to solidify and insolubilize the pollutants in the soil. Contaminants remain in the soil, and the contaminants in the soil cannot be reduced, and reliable safety cannot be expected.

  In biological methods, in order for plants to absorb pollutants, it takes a long time to repair the environment, and during that time, it is necessary to continue to manage contaminated soil and plants. Furthermore, there is a problem that it is necessary to treat the plant that has absorbed the pollutant, and it takes time and effort to realize it. In addition, because it absorbs pollutants in the soil from the roots of the plants, depending on the type of plants that remain on the soil surface, it is difficult to absorb pollutants that remain within a depth of about 5 cm from the soil surface. When the plant cannot be removed, or when the plant is removed, the roots may break in the soil due to the frictional force with the soil and leave behind.

  The present invention can remove the contaminated soil surface layer contaminated by heavy metals, particularly radioactive materials in the atmosphere, quickly and reliably, and at the lowest cost, reduce the waste as much as possible and reduce the burden after the removal process. It is an object of the present invention to provide a method for removing the contaminated soil surface layer, which can reduce the amount of water and can secure the safety of the installer. Moreover, the construction method which removes a contaminated soil surface layer using the self-propelled construction machine which can remove the contaminated soil surface layer of a thin range stably and is easy for an operator to operate is provided.

  As a result of repeated studies to solve the above problems, the present inventors have found that when the soil is contaminated by heavy metals contained in irrigation water or radioactive materials in the atmosphere, the contaminant is about a depth from the soil surface. Focusing on staying on the surface layer within 5 cm, without mixing the solidifying agent with the soil, the solidifying agent is sprayed on the soil surface as a slurry-like solidifying material, and this soil-solidifying mixture is mixed with the soil. It has been found that the above-mentioned problem can be solved by infiltrating the soil surface layer without solidifying, solidifying the soil surface layer, and peeling only the soil surface layer including the solidified soil portion.

  Furthermore, using a self-propelled construction machine with a working part for stripping the surface of the soil, the working part of this self-propelled construction machine is placed at a depth to peel off the soil surface, and the working part is parallel to the soil surface. It was found that the soil surface layer of the target thickness can be peeled off by sliding it on the surface.

[1] The present invention includes (1) a step of spraying a slurry solidifying slurry material containing a solidifying agent and a liquid on the soil surface; and (2) a soil solidifying slurry material sprayed on the soil surface on the soil surface. A method for removing the contaminated soil surface layer comprising the steps of infiltrating the shallow layer region and solidifying the soil surface layer; and (3) a step of stripping the soil surface layer including the soil portion solidified by the slurry material for soil solidification. About.
[2] In the present invention, the solidifying agent is at least one solidifying agent selected from the group consisting of a magnesia-based solidifying agent, a cement-based solidifying agent, a calcium-based solidifying agent, a lime-based solidifying agent, and a gypsum-based solidifying agent. The present invention relates to a method for removing a contaminated soil surface layer according to [1].
[3] The contaminated soil according to [1] or [2], wherein the solidifying agent is a magnesia-based solidifying agent, and the magnesia-based solidifying agent contains 5 to 99% by mass of magnesium oxide in a total amount of 100% by mass. It relates to a surface layer removal method.
[4] The above-mentioned [1], wherein the solidifying agent has a brain specific surface area of 4,000 to 8,000 cm ² / g, and the soil solidifying slurry material contains 200 to 800 parts by mass of liquid with respect to 100 parts by mass of the solidifying agent. [3] The method for removing a contaminated soil surface layer according to any one of [3].
[5] The present invention disperses the soil solidified slurry material containing the magnesia-based solidifying agent on the soil surface to discolor the solidified soil portion so that it can be visually confirmed. It is related with the removal construction method of the said [3] or [4] description which peels off the soil surface layer containing the solidified soil part, confirming.
[6] The present invention relates to a method for removing a contaminated soil surface layer according to any one of the above [1] to [5], wherein a slurry material for solidifying a soil is sprayed, sprayed, or sprayed by dripping by rain dew.
[7] The present invention relates to the method for removing a contaminated soil surface according to any one of [1] to [6], wherein the thickness of the soil surface to be peeled is 10 cm or less.
[8] The present invention relates to the method for removing a contaminated soil surface according to any one of [1] to [7], wherein the thickness of the soil surface layer to be peeled is 1 to 4 cm.
[9] The present invention uses a self-propelled construction machine provided with a working part for stripping the soil surface layer, arranges the working part at a depth at which the soil surface layer is stripped, and the working part is parallel to the soil surface. It is related with the removal construction method of the contaminated soil surface in any one of said [1]-[8] which is made to slide and peels off the soil surface layer containing the solidified soil part of the area | region where a working part slides.
[10] The present invention relates to the method for removing a contaminated soil surface according to the above [9], which includes a step of depositing the peeled soil surface layer in a region where the sliding of the working part stops.
[11] In the present invention, after the step of depositing, the self-propelled construction machine is moved, and the step of peeling off the soil surface layer and the step of depositing the peeled soil surface layer are repeated at least once and peeled off. The present invention relates to a method for removing a contaminated soil surface layer according to the above [9] or [10], wherein the contaminated soil surface layer is made into a streak-removed pile.
[12] The present invention relates to a method for removing a contaminated soil surface according to any one of the above [1] to [11], which includes a step of sucking and collecting the peeled soil surface layer.
[13] In the present invention, any one of the above [9] to [12], wherein the working unit of the self-propelled construction machine is a bucket, and the bucket has an edge portion protruding from the bucket and disposed in the contaminated soil. It is related with the removal construction method of the contaminated soil surface layer described in 1.
[14] The present invention according to any one of [9] to [13], wherein the self-propelled construction machine includes a soil collection container and a carry-out means for carrying out the soil surface layer peeled off by the soil collection container. It relates to a method for removing contaminated soil surface.

  According to the present invention, a slurry material for solidifying a slurry containing a solidifying agent and a liquid is sprayed on the soil surface, and the dispersed soil solidifying slurry material is infiltrated into the soil without mixing, so that from the surface of the soil. It is possible to solidify up to a region where the slurry material for soil solidification has permeated, and to effectively peel only the soil surface layer including the solidified soil portion. According to the present invention, since only a relatively thin surface layer of the soil can be effectively peeled off, soil contaminated with pollutants such as heavy metals contained in irrigation water and radioactive materials in the atmosphere, In particular, by applying to soil contaminated with radioactive material, the contaminated soil surface layer can be removed quickly and reliably. According to the present invention, since only the contaminated soil surface layer is removed, construction can be easily performed, the amount of soil to be removed can be reduced as much as possible, the construction cost is reduced, and the processing burden after removal is also reduced. be able to. Furthermore, according to the present invention, the soil surface layer where the pollutant remains, particularly the soil surface is solidified, and only the soil surface layer including the solidified soil portion is peeled off. It can suppress, it can suppress that dust etc. generate | occur | produce at the time of construction, it can suppress that a pollutant disperses with generation | occurrence | production of dust, and it can ensure a worker's safety.

  According to the present invention, using a self-propelled construction machine, the working part provided in the self-propelled construction machine is disposed at a depth to be peeled off, and the working part is slid in parallel with the soil surface, Since the surface layer is peeled off, it is possible to suppress the increase in the depth at which the working part is inserted into the soil, and to stabilize the thinned layer within the thin layer for the purpose of peeling off the soil surface. In addition, the operator operating the self-propelled construction machine can visually recognize how far the working unit has been arranged. Furthermore, the operation of the working unit by the operator can be slid in parallel with the soil surface, that is, can be an easy work of turning left and right, and the difficulty of operating the working unit can be suppressed.

It is a graph which shows the relationship between the depth (cm) in a soil, and radioactive cesium density | concentration (Bq / kg). It is a photograph which shows the embodiment which shows the embodiment of this invention and has spread | dispersed the soil solidification slurry material containing a solidifying agent on the soil surface (1 m < ² >). It is a photograph which shows the embodiment of this invention and shows the state which peels off the soil surface layer containing the solidified soil part manually with a scoop. It is a photograph which shows the state which shows the embodiment of this invention and measures the thickness of the peeled soil surface layer. It is a photograph which shows the embodiment of this invention and shows the state which measures the radiation dose in the air of the height of 5 cm from the soil surface after peeling off the soil surface layer. It is a photograph which shows the embodiment of this invention, and shows the spraying machine and generator for spraying the slurry material for soil solidification containing a solidification agent over a wide range (for example, 10 m < ² > or more). It is a photograph which shows the embodiment of this invention and shows the state which is spraying the soil material for soil solidification containing a solidification agent on the soil surface (225m < ² >: Example 5) with a spraying machine. It is a photograph which shows the application | coating state of a solidification agent. It is a photograph which shows the state which shows the embodiment of this invention and measures the thickness of the soil surface layer peeled off from some test soil. It is a photograph which shows the embodiment which shows the embodiment of this invention and shows the state which measures the thickness of the soil surface layer peeled off from some test soils (parts different from the site | part of FIG. 8). It is a photograph which shows the embodiment which shows the embodiment of this invention and shows the state which measures the thickness of the soil surface layer peeled off from some test soils (parts different from the site | part of FIG. 8 or FIG. 9). It is a photograph which shows the embodiment which shows the embodiment of this invention and shows the state which measures the thickness of the soil surface layer peeled off from some test soils (parts different from the site | parts of FIGS. 8-10). It is a figure which shows the state which attached the bucket of 1st Embodiment applicable to this invention to the front-end | tip part of a hydraulic shovel, (a) shows a front view, (b) shows a side view, (c) shows A top view is shown, and the case where it is made to turn right and left by a dotted line is shown. It is a figure which shows the case where the bucket of 1st Embodiment is earth | grounded and it is made to turn from right to left toward the advancing direction, (a) arrange | positions a bucket in the removal start end of the right in the area | region which removes a soil surface layer, and It is a figure which shows the state which grounded and started turning, (b) It is a figure which shows the state which reached the intermediate point of turning, (c) The figure which shows the state which reached the end edge part of turning It is. FIGS. 13A and 13B are photographs of actual experiments corresponding to the states of FIGS. 13A and 13B, FIG. 13A is a photograph corresponding to the state of FIG. 13A, and FIG. It is a photograph corresponding to the intermediate state of b), (c) is a photograph corresponding to the intermediate state of FIG. 13 (b) and FIG. 13 (c), and (d) is the state of FIG. 13 (c). (E) is an enlarged photograph of the inside of the square frame of the region 19 in FIG. 13 (b). BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows embodiment of the bucket to which the edge part applicable to this invention was attached, (a) A plate-shaped edge part is attached so that the left view may protrude substantially perpendicularly with respect to the soil surface from a bucket. The side view showing the bucket in a state in which it has been formed, the right side view is a front view of the left side view as seen from the opening direction of the bucket, and the left side view protrudes substantially perpendicular to the soil surface from the bucket, and from the back plate of the bucket The plate-like first edge portion is attached so as to protrude, and the plate-like second edge portion is attached so as to protrude substantially horizontally with respect to the soil surface from the bottom opening side end portion of the bucket. The side view showing the bucket of Fig. 2, the right side view is a front view of the left side view as viewed from the opening direction of the bucket, and (c) the left side view is two plate-shaped so as to protrude substantially perpendicular to the soil surface from both sides of the bucket. The edge part is attached Side view of the bucket of a state, a front view of the right side view is viewed left side view from the opening direction of the bucket. It is a figure which shows the state which attached the bucket of 2nd Embodiment applicable to this invention to the front-end | tip part of a hydraulic shovel, (a) shows a front view, (b) shows a side view, (c) shows A top view is shown, and the case where it is made to turn right and left by a dotted line is shown. It is a figure which shows the state which attached the bucket of 3rd Embodiment of this invention to the front-end | tip part of the hydraulic shovel, (a) shows a front view, (b) shows a side view, (c) shows a top view. The figure shows the case of turning left and right with a dotted line. It is the figure which expanded the bucket part of FIG. 17, (a) shows a side view, (b) shows a front view, (c) shows a top view. It is a figure which shows the whole structure of 3rd Embodiment applicable to this invention.

  The present invention includes (1) a step of spraying a slurry-like solidifying slurry material containing a solidifying agent and a liquid on the soil surface without mixing the solidifying agent with the soil, and (2) soil solidifying sprayed on the soil surface. Removal of contaminated soil surface, including the step of infiltrating the slurry material for soil into the shallow layer region of the soil to solidify the soil surface layer, and the step of (3) stripping the soil surface layer including the soil portion solidified by the slurry material for soil solidification It is a construction method. Hereinafter, the steps (1) to (3) will be described in detail.

[(1) Process of applying slurry material for soil solidification to soil surface]
In the step of (1) applying the soil solidifying slurry material to the soil surface of the present invention, the soil solidifying slurry material is a slurry containing a solidifying agent and a liquid. The solidifying agent used in step (1) of the present invention is not particularly limited as long as it can be used for solidifying soil, and commercially available solidifying agents that are generally used can be used. As the solidifying agent, it is preferable to use at least one solidifying agent selected from the group consisting of a magnesia based solidifying agent, a cement based solidifying agent, a calcium based solidifying agent, a lime based solidifying agent and a gypsum based solidifying agent. A solidifying agent may be used individually by 1 type, and may use 2 or more types together.

  The magnesia-based solidifying agent contains magnesium oxide, and the content of magnesium oxide in 100% by mass of the magnesia-based solidifying agent is preferably 5 to 99% by mass, more preferably 10 to 90% by mass, and still more preferably. It is 15-80 mass%, Most preferably, it is 15-55 mass%. In addition, the magnesia-based solidifying agent may include, for example, phosphate, gypsum, and oxycarboxylic acid as a soil hardening agent. The magnesia-based solidifying agent combines with moisture in the soil to form magnesium hydroxide and becomes a gel, and then reacts with phosphoric acid in the soil or carbon dioxide in the air to react with magnesium phosphate or basic magnesium carbonate The soil surface layer can be temporarily or non-temporarily solidified.

  The magnesia-based solidifying agent generally has a pH range suitable for growing crops, preferably pH 5-11, more preferably pH 8-11, without tilting the pH of the sprayed soil to the strong alkali side like a cement-based solidifying agent. More preferably, since the soil surface layer can be solidified so as to have a pH of 9 to 11, it can be suitably used in soil where crop productivity such as paddy fields, farmland, and pastures is desired to be maintained.

  The magnesia-based solidifying agent can be discolored so that the solidified soil surface can be visually confirmed. Specifically, the magnesia-based solidifying agent is white and solidified so that the solidified soil surface can be visually confirmed by spraying the soil-solidifying slurry material containing the magnesia-based solidifying agent on the soil surface. The soil portion can be turned white. As described above, according to the present invention, the soil surface layer including the solidified soil portion is peeled off while confirming the surface of the soil solidified by visual observation by dispersing the soil solidifying slurry material containing the magnesia-based solidifying agent on the soil surface. It has the advantages of being easy to construct and having no unremoved parts.

Examples of the cement-based solidifying agent include compositions containing Portland cement, blast furnace cement, and early-strength cement. The cement-based solidifying agent may contain anhydrous gypsum, dihydrate gypsum, hemihydrate gypsum, slaked lime, lime and the like in addition to Portland cement and the like. The cement-based solidifying agent may contain lignin sulfonates, polycarboxylates, melamine sulfonates, etc. in the composition as, for example, a water reducing agent or a dispersant. Examples of the calcium-based solidifying agent include a composition containing quick lime (CaO) and slaked lime (Ca (OH) ₂ ) as main components. The lime-based solidifying agent includes a composition containing calcium carbonate (CaCO ₃ ) as a main component. Examples of the gypsum solidifying agent include a composition containing, as a main component, at least one selected from the group consisting of dihydrate gypsum, hemihydrate gypsum, and anhydrous gypsum. The cement-based solidifying agent may increase the pH of the soil. After the slurry solidifying slurry material mixed with the solidifying agent and liquid to form a slurry is sprayed on the soil surface, It may be necessary to neutralize.

  The solidifying agent is preferably dispersed uniformly on the surface of the soil to be treated, and a solidifying agent such as powder, slurry, or liquid can be dispersed. In the present invention, the solidifying agent and liquid are dispersed. It is preferable to disperse the slurry-like slurry material for solidifying soil. The liquid used to make the solidifying agent into a slurry can be pure water, tap water, or the like. The ratio of the solidifying agent and the liquid of the slurry material for solidifying the soil can be appropriately adjusted depending on the kind of the solidifying agent and the like, and can also be appropriately adjusted depending on the Blaine specific surface area of the solidifying agent. If there is too much liquid relative to the solidifying agent, the soil becomes saturated and the solidifying agent may not penetrate into the soil. When the liquid is water (tap water), the ratio of the solidifying agent and the liquid of the slurry material for soil solidification is preferably 100 to 1,000 parts by mass of water, more preferably water with respect to 100 parts by mass of the solidifying agent. It is 200-900 mass parts, More preferably, it is 200-800 mass parts, Most preferably, it is 200-600 mass parts.

In order for the slurry material for soil solidification to penetrate from the soil surface to a depth of preferably 10 cm or less, more preferably 5 cm or less, even more preferably 1 to 4 cm, particularly preferably 3 cm or less from the soil surface. The Blaine specific surface area is preferably 3,000 to 12,000 cm ² / g. When using a magnesia-based solidifying agent, the brane specific surface area of the solidifying agent is more preferably 3,500 to 10,000 cm ² / g, still more preferably 4,000 to 8,000 cm ² / g, particularly preferably 4. , 000 to 6,000 cm ² / g. When the solidifying agent is a magnesia-based solidifying agent, if the Blaine specific surface area is within the above range, the depth is preferably 10 cm or less, more preferably 5 cm or less, and further preferably 1 to 4 cm from the soil surface. Particularly preferably, the solidifying agent can be infiltrated to a depth of 3 cm or less. As the Blaine specific surface area of the solidifying agent increases, the particle size decreases, and the solidifying slurry material containing the solidifying agent and liquid easily penetrates into the soil, and the solidifying agent penetrates to a deeper range and contaminates at a suitable thickness. While it becomes possible to peel off the soil surface layer, the construction cost may be expensive. When using at least one solidifying agent selected from the group consisting of a cement-based solidifying agent, a calcium-based solidifying agent, a lime-based solidifying agent, and a gypsum-based solidifying agent, the brane specific surface area of the solidifying agent is more preferably 3,500~11,000cm ² / g, more preferably from 4,000~10,000cm ² / g.

The ratio of the solidifying agent to the liquid in the slurry material for soil solidification varies depending on the depth at which the solidifying agent penetrates into the soil from the soil surface, and preferably 10 cm or less from the soil surface. Preferably when the solidifying agent is infiltrated into the soil within a depth of 5 cm or less, more preferably 1 to 4 cm, particularly preferably 3 cm or less, and the brain specific surface area of the solidifying agent is 4,000 to 8, 000 cm ² / g and when the liquid is tap water, the ratio of the solidifying agent and the liquid in the slurry material for solidifying the soil is 200 to 800 parts by mass of the liquid with respect to 100 parts by mass of the solidifying agent. Preferably, it is 200 to 600 parts by mass, more preferably 200 to 500 parts by mass, and particularly preferably 300 to 400 parts by mass. Moreover, it is a case where the slurry material for soil solidification containing a solidifying agent and a liquid is infiltrated into a depth of 1 to 4 cm, preferably about 3 cm from the soil surface, and the brane specific surface area of the solidifying agent is 4,000 to 6 a 000cm ² / g, when the liquid is tap water, the ratio of the solidifying agent and liquid soil solidifying the slurry material in the relative solidifying agent 100 parts by weight, the liquid is 200 to 600 parts by weight More preferably, it is 200-500 mass parts, More preferably, it is 300-400 mass parts.

The method for spraying the soil solidifying slurry material on the soil surface is not particularly limited, but it is preferably sprayed by spraying with a sprayer, spraying with a power spraying device or the like, or dripping by rain dew. Spraying with a spraying machine or spraying with a power spraying device can be applied when the area to which the soil solidifying slurry material is sprayed is large (for example, the soil surface is 10 m ² or more). This can be applied when the area to be sprayed is small (for example, the soil surface is less than 10 m ² ). FIG. 2 shows one embodiment of the step (1) of the present invention. A soil solidifying slurry A containing a solidifying agent and a liquid is applied to a region of an area of 1 m ^{2 on} the soil surface of paddy soil C1, which is a farm field. It is a photograph which shows the state currently sprayed by. FIG. 6 is a photograph showing an overview of the generator and sprayer used when the soil solidifying slurry A1 is sprayed onto the soil surface. FIG. 7 shows another embodiment of the step (1) of the present invention, in which a soil solidifying slurry A2 containing a solidifying agent and a liquid is an area having an area of 1225 m ^{2 on} the soil surface of paddy soil B2 as a field. It is a photograph which shows the state sprayed by spraying machine B2.

[(2) Infiltration of solidifying agent, solidifying soil surface]
The step (2) of the present invention is a step of solidifying the soil surface layer by allowing the soil solidifying slurry material spread on the soil surface to penetrate into the shallow layer region of the soil surface.

  As shown in FIG. 1, pollutants, for example, radioactive cesium, is 95% at a depth of 2.5 cm from the soil surface when the farm field is unplowed farmland soil.

  In order to solidify the soil surface layer where pollutants, particularly radioactive substances in the atmosphere remain, the soil solidifying slurry material is preferably at least 10 cm deep, more preferably 5 cm deep, and even more preferably 1 depth from the soil surface. It is preferable to use one that penetrates to a range of ˜4 cm, particularly preferably a depth of 3 cm or less. The permeability of the soil solidifying slurry material to the soil also affects the soil quality (viscous soil, sandy soil, etc.) and the moisture in the soil, so the hydraulic conductivity of the soil and the soil particles that make up the soil In consideration of the particle size, etc., the type of solidifying agent in the slurry material for solidifying the soil, the Blaine specific surface area of the solidifying agent, and the mixing ratio of the solidifying agent and the liquid are appropriately selected so that the slurry material for solidifying the soil It is preferable to adjust the penetration depth.

  After the soil solidifying slurry material sprayed on the soil surface has penetrated from the soil surface, preferably within a depth of 10 cm, more preferably within a depth of 5 cm, more preferably within a depth of 1 to 4 cm, particularly preferably within a depth of 3 cm, The number of days required for solidification of the soil surface layer infiltrated with the slurry material for soil solidification varies depending on the applied solidifying agent, its concentration, type of soil, etc., but when magnesia-based solidifying agent is used, Six hours after spraying the slurry material, solidification of the soil surface begins, and external factors such as temperature, rainfall, and soil temperature, soil properties, soil quality, etc., until sufficient strength to enable stripping occurs. Due to the internal factors, a curing period of about 2 to 10 days is required. The soil surface is solidified with a soil-solidifying slurry that contains a solidifying agent during or after curing, so it is possible to prevent contaminants from flowing out of the soil due to rainfall and scattering of dust with the dust generated by the wind. Is possible. In addition, the strength that can be peeled off means that it remains on the ground surface of the solidified soil surface with a shovel or excavator in the case of manual labor, a hydraulic shovel, loader, bulldozer or grader in the case of heavy machinery. It is said that it has a strength that can peel off only the soil surface layer including the root system of the plant stalk and the plant in the surface layer, and the slurry material for solidifying the slurry containing the solidifying agent and the liquid was sprayed It is not required that the soil surface layer has a strength that can be peeled off as a single plate. In addition, the solidified soil surface layer only needs to be temporarily solidified to such an extent that it can be peeled off, and the strength is not required to maintain the solidified state until after being peeled off.

[(3) Process of peeling off the soil surface layer including the solidified soil part]
Step (3) of the present invention is a step of stripping the soil surface layer including the soil portion solidified by the soil solidifying slurry material. When the area to be peeled is small (for example, less than about 10 m ² ), the soil surface layer may be peeled off manually using a scoop or the like. FIG. 3 is a photograph showing an embodiment of the present invention and showing a state in which a soil surface layer D1 including a soil portion solidified by a soil solidifying slurry material is peeled off using a scoop E1. In FIG. 3, the soil solidified slurry material is sprayed and the solidified soil portion has turned white, and the soil surface C1 ′ from which the whitened soil surface layer D1 has been peeled off has a soil color. There is no remaining of the surface layer D1. In the case the area to strip is large (e.g., about 10 m ² or more), disposed bulldozers, loaders, using self-propelled construction machine such as a hydraulic excavator or grader, a working unit such as a bucket depth strip the soil surface Then, it is preferable that the working surface such as a bucket is slid in parallel with the soil surface, and the soil surface layer including the solidified soil portion in the region where the working portion slides is peeled off.

  When the pollutant is, for example, radioactive cesium, as shown in FIG. 1, since 95% exists at a depth of 2.5 cm from the soil surface, the thickness of the soil surface to be peeled is preferably 10 cm or less, More preferably, the soil surface layer is peeled off so as to be 5 cm or less, more preferably 1 to 4 cm, and particularly preferably 3 cm or less. In particular, in order to peel off the soil surface layer within a depth of 10 cm, more preferably within a depth of 5 cm, even more preferably within a depth of 1 to 4 cm, and particularly preferably within a depth of 1 to 3 cm, from the soil surface contaminated with a contaminant. For example, it is preferable to slide the front working part such as a bucket of a self-propelled construction machine such as a hydraulic excavator in parallel with the soil surface to peel off the soil surface layer.

  Conventionally, working machines such as tractors used in farmland etc. have levelers and graders as attachments, and there are those that move these attachments back and forth as the tractor is driven. It can be used in (3). However, in order to avoid the soil surface layer being stepped on by the tires, the contamination of the contaminated soil surface layer, and mixing with the soil below the contaminated soil surface, in step (3) of the present invention For example, it is preferable to use a front working unit such as a bucket of a self-propelled construction machine such as a hydraulic excavator.

  In the step (3) of the present invention, as a self-propelled construction machine, for example, a hydraulic excavator is used, and a bucket is used as a working part, and the working part is disposed at a depth at which the soil surface layer is peeled off. Soil surface layer containing the solidified soil part of the area where the working part slides by sliding in parallel with the soil surface, that is, by swinging the bucket horizontally to the left and right like a wiper in parallel with the soil surface Can be peeled off.

  The peeled soil surface layer preferably has a thickness of 10 cm or less, more preferably 5 cm or less, still more preferably 1 to 4 cm, and particularly preferably 1 to 3 cm. 4 and 8 to 11 are photographs obtained by measuring the thickness of the peeled soil surface layer. As shown in FIGS. 4 and 8 to 11, when measured in consideration of some unevenness, the thickness of the soil surface layers D 1 and D 2 including the solidified soil portions D 1 ′ and D 2 ′ peeled off is about 2.5. ~ 3.5 cm. When the thickness of the peeled soil surface layer is 10 cm or less, the soil surface layer contaminated by heavy metals in irrigation water and radioactive materials in the atmosphere can be surely removed from the soil, and safety is improved. The thickness of the soil surface layer to be stripped is 5 cm or less, more preferably the thickness of the soil surface layer to be stripped is 1 to 4 cm, and more preferably the thickness of the soil surface layer to be stripped is 1 to 3 cm Along with the improvement of the property, it is possible to remove only the surface layer of the soil where the contaminants such as radioactive substances in the atmosphere stay, and to reduce the amount of soil to be removed, thereby reducing the construction cost.

  According to the step (3) of the present invention, unlike the other soil not coated with the soil solidifying slurry material, the soil surface layer including the soil portion solidified by the soil solidifying slurry material in advance is peeled off. It is easy to remove and is less likely to be left behind. Furthermore, since the soil surface layer including the solidified soil portion is peeled off, generation of dust during the stripping operation can be suppressed, and scattering of pollutants contained in the soil surface layer can be suppressed as the dust is rolled up. The safety of the installer can be ensured.

  Furthermore, when using a slurry material for soil solidification containing a magnesia-based solidifying agent and stripping the soil surface layer including the previously solidified soil portion, the soil is removed by the magnesia-based solidifying agent contained in the slurry material for soil solidification. Since the soil portion turns white so that the portion can be visually confirmed, and the soil surface layer can be peeled off while visually confirming, there is no leftover and the construction is easy.

  The removal method of the soil surface layer of the present invention includes a step (4) of depositing the peeled soil surface layer in a region where sliding of the working part stops after the step (3) of stripping the soil surface layer including the solidified soil portion. It is preferable to include.

  Furthermore, when using a self-propelled construction machine, the process of removing the soil surface layer including the solidified soil part by moving the self-propelled mobile machine after the step (4) of depositing the peeled soil surface layer (3) and the step (4) of depositing the peeled soil surface layer in the region where the sliding of the working part stops are repeated at least once, and the polluted soil surface layer stripped off is deposited on the streak-removed soil embankment as an example. It is preferable to include the process to make. Furthermore, it is preferable to include a step (5) of sucking and collecting the peeled soil surface layer.

  Next, the self-propelled construction machine provided with the working part used for the method for removing the contaminated soil surface layer of the present invention, the step (3) of stripping the soil surface layer using the self-propelled construction machine, A process including the step (4) of depositing the soil surface layer and the step (5) of sucking and collecting the peeled soil surface layer will be described.

As a method for removing the contaminated soil surface layer, a bucket can be applied as the following collection method and working unit.
[1] A step of placing a bucket attached to a self-propelled construction machine capable of turning left and right in a region where a soil surface layer is removed, a step of grounding the bucket to the soil surface layer, and A method for peeling and collecting the soil surface layer, characterized in that the method comprises a step of turning in the direction in which the right and left turn is possible in a state where the surface is grounded.
[2] The bucket has a flat bottom surface, an edge is formed at a tip of the bottom surface in the turning direction, the bottom surface has at least one plate in an upright direction, and the bucket is grounded. The method for stripping and collecting the soil surface according to [1], wherein the bottom surface is grounded to the soil surface.
[3] In the bucket, the bucket opening is directed in the turning direction, the upright plate is a back plate, and in the turning step, the soil peeled off from the soil surface layer is the bucket opening. The method for stripping and collecting the soil surface layer according to [1] or [2], wherein the soil surface layer is guided into the bucket.
[4] The bucket is connected to unloading means extended to at least a soil collection container, and in the turning step, the soil of the bucket is accumulated in the soil collection container via the unloading means. 3] Stripping and collecting method of soil surface layer.
[5] The bucket is provided with a crushing device for crushing the soil, and in the turning step, the crushed soil is guided into the bucket, and the soil surface is peeled and collected according to [4] Construction method.
[6] The crushing device includes a plurality of blades attached to a motor-driven rotating shaft, and the crushing is performed by rotating the rotating shaft. Stripping collection method.
[7] The method for stripping and collecting the soil surface layer according to any one of [4] to [6], wherein a water supply hose for supplying water is connected to the bucket or the carry-out means to supply water to the soil.
[8] A bucket attached to a self-propelled construction machine capable of turning left and right, which is formed of a flat surface and has a bottom surface with an edge formed at a tip of the turning direction, and a bucket opening portion directed in the turning direction And an opening for suction provided in a back plate formed in an upright direction from the bottom surface, and a crushing device for crushing the soil peeled off from the soil surface, the opening for suction being carried out A bucket formed so that means can be connected.
[9] The bucket according to [8], wherein the crushing device includes a rotation shaft to which a plurality of blades are attached, and a motor that drives the rotation shaft.
[10] The bucket according to [8] or [9], wherein the crushing device further includes a screw conveyor that guides the crushed soil to the suction opening.
[11] The bucket according to any one of [8] to [10], wherein the bucket or the carry-out means includes a water supply hose connection portion for supplying water therein.
[12] The bucket according to any one of [1] to [11], including an edge portion attached so as to protrude from the bucket.

  [1] In a soil surface peeling and collecting method according to an embodiment applicable to the present invention, a step of placing a bucket attached to a self-propelled construction machine capable of turning right and left in a region where the soil surface layer is removed; And a step of grounding the bucket to the soil surface layer, and a step of pivoting the bucket in a direction in which the bucket can be turned to the left and right while being grounded to the soil surface layer. By rotating the bucket attached to the self-propelled construction machine to the left and right, the bucket is slid in parallel to the soil surface, that is, the bucket is swung to the left and right like the wiper in the horizontal direction in parallel with the soil surface. By this, it is possible to peel off the soil surface layer including the solidified soil portion of the region where the working unit slides

  According to the stripping and collecting method of the soil surface layer of this embodiment, the bucket is grounded to one of the left and right removal start ends in the region where the soil surface layer is removed, and the bucket is grounded to the soil surface layer. Using the left and right turning motion of the traveling construction machine, the soil surface layer is peeled off in the horizontal direction by turning in one of the directions that can turn left and right. This operation is performed by temporarily stopping the self-propelled construction machine at the stripping position and turning only the bucket in the lateral direction in a stable state. Therefore, when the soil is stripped while self-propelled as in the past or when the operator operates the bucket in the direction opposite to the self-propelled direction or the self-propelled direction, The bucket does not go too deep into the stripping layer. As a result, the soil to be peeled can be thinly stabilized only on the surface layer. In addition, the operation of turning only the bucket in the horizontal direction is performed when the operator can visually check the state of the soil surface layer into which the edge of the bucket or the edge protruding from the bucket is inserted, and conventionally leveling the soil with a hydraulic excavator. Therefore, the work can be performed relatively easily.

  [2] Preferably, in one embodiment of the soil surface stripping and collecting method applicable to the present invention, the bucket has a flat bottom surface, an edge is formed at the tip in the swiveling direction on the bottom surface, and the bucket is upright on the bottom surface. In the step of having at least one plate in the direction and grounding the bucket, the bottom surface may be grounded to the soil surface layer.

  In this embodiment, the bottom surface of the bucket is a flat surface and the flat surface is grounded. As a result, the flat portion of the bottom surface of the bucket stabilizes the bottom edge of the bucket so that it is not inserted too much into the soil surface when the bucket is swung in contact with the soil surface, and the bucket sinks excessively. It can suppress so that it may not enter. Therefore, the soil surface layer can be thinly and stably peeled off. Moreover, the front end side in the traveling direction of the turning in the plane of the bottom surface becomes an edge perpendicular to the turning direction, and the soil surface layer can be peeled off at the edge. Moreover, since it has the board arrange | positioned in the upright direction from the bottom face, the soil stripped off by the upright board can be pushed and conveyed in the advancing direction.

  [3] Preferably, in the soil surface peeling and collecting method according to one embodiment applicable to the present invention, the bucket is directed in the direction in which the bucket opening is swung, the upright plate is the back plate, In the step of causing the soil to peel off from the soil surface layer, the soil may be guided into the bucket from the bucket opening.

  In this embodiment, the bucket opening is directed in the direction of rotation, and the soil peeled off from the soil surface is guided into the bucket and stopped by the back plate, so until the capacity of the bucket is full, The stripped soil will not spill. As a result, it is possible to increase the amount of the peeled soil that is pushed in the traveling direction, and to reduce the amount of spilling from the front surface of the bucket.

  [4] Preferably, in the method for stripping and collecting the soil surface layer according to one embodiment applicable to the present invention, the bucket is connected to unloading means extended to at least a soil collection container, and in the step of turning, the bucket soil is However, you may make it accumulate | store in a soil collection container via a carrying-out means.

  In this embodiment, the unloading means connected to the vacuum suction device (or vacuum car) is connected to the bucket, and the soil guided into the bucket is directly discharged into the unloading means without delay, Move to the soil collection container. Therefore, once collected on the side of the traveling direction of the self-propelled construction machine and then collected and transported together, or the stripped soil guided in the bucket Compared to dropping and collecting on the platform of a transport vehicle, the amount of spilled soil from the front of the bucket can be further reduced, reducing the process of collecting and transporting the removed soil from the collection location. can do. As a result, it is possible to increase the continuity of the collection and removal of the soil surface layer by reducing the time for interrupting the removal and collection of the soil surface layer and the accompanying work. As a result, efficiency can be improved by reducing time and man-hours, and work can be performed safely.

  [5] Preferably, in the soil surface peeling and collecting method according to one embodiment applicable to the present invention, the bucket is provided with a crushing device for crushing the soil. It may be guided inside.

  In this embodiment, a crushing device is provided in the bucket and the peeled soil is crushed and sucked, so when the soil is naturally or intentionally hardened due to a large amount of water or clay, Reduces the suction efficiency due to soil staying in the unloading means, and makes it impossible to suck the soil due to clogging of the unloading means, and canceling the stripping and collecting work for its recovery. . As a result, interruption for maintenance of the unloading means can be reduced, the efficiency can be improved, and the continuity of the stripping and collecting operation can be improved.

  [6] Preferably, in the soil surface peeling and collecting method according to one embodiment applicable to the present invention, the crushing device is configured by attaching a plurality of blades to a motor-driven rotating shaft, and crushing is rotated. It may be implemented by rotating the shaft.

  In this embodiment, the crushing device is driven by a rotary blade so that the rotational speed of the blade attached to the rotary shaft is sufficiently faster than the speed at which the soil is introduced into the bucket. Thereby, even if it is a case where the peeled soil is solidified, the soil can be crushed continuously. As a result, the efficiency of the soil stripping and collecting operation can be improved.

  [7] Preferably, in the method for stripping and collecting the soil surface layer according to one embodiment applicable to the present invention, a water supply hose for supplying water to the inside of the bucket or the carrying-out means is connected to supply water to the soil. Good.

  In this embodiment, when the crushed soil contains water and has a high viscosity and is difficult to suck, the water content is further increased by supplying water from the water supply hose to the highly viscous soil, thereby reducing the viscosity. Can be made. With this water supply, the viscosity of the soil decreases, so that the soil stays in the unloading means and the suction efficiency drops, and the unloading means becomes clogged and the soil cannot be sucked. Stopping collection work can be reduced. As a result, it is possible to reduce the interruption of the soil stripping and collecting work for the maintenance of the carrying-out means, to improve the efficiency, and to improve the continuity of the work.

  [8] In order to solve the above-described problem, a bucket according to an embodiment applicable to the present invention is a bucket attached to a self-propelled construction machine capable of turning left and right, formed in a plane, A bottom surface with an edge formed at the tip, a bucket opening directed in the swiveling direction, a suction opening provided in a back plate formed in an upright direction from the bottom surface, and soil removed from the soil surface And a suction opening is formed so that the carrying-out means can be connected.

  According to the bucket of this embodiment, a crushing device that crushes the peeled soil is provided in the bucket, and the carry-out means is connected. The soil peeled off from the soil surface is crushed by a crushing device and then sucked. As a result, when the soil is hardened, the soil stays in the unloading means, or the soil suction efficiency decreases or cannot be sucked, and the stripping and collecting work is stopped for recovery. Can be reduced. As a result, interruption for maintenance of the unloading means can be reduced, the efficiency can be improved, and the continuity of the stripping and collecting operation can be improved.

  [9] Preferably, in the bucket according to an embodiment applicable to the present invention, the crushing device may include a rotating shaft to which a plurality of blades are attached and a motor for driving the rotating shaft.

  In this embodiment, the crushing device has a motor that drives the rotary blade so that the rotational speed of the blade attached to the rotary shaft is sufficiently faster than the speed at which the soil is introduced into the bucket. Thereby, even if it is a case where the peeled soil is solidified, the soil can be crushed continuously. As a result, the efficiency of the soil stripping and collecting operation can be improved.

  [10] Preferably, in the bucket according to an embodiment applicable to the present invention, the crushing device may further include a screw conveyor for guiding the crushed soil to the suction opening.

  In this embodiment, the crushed soil in the bucket can be guided to the suction opening without delay with a screw conveyor that is arranged in a guiding direction and is motor-driven. This reduces the amount of crushed soil that stays in the bucket, making it easier for soil to be stripped into the bucket and reducing resistance to scraping and collecting work on the soil surface, improving work efficiency be able to.

  [11] Preferably, in the bucket according to one embodiment applicable to the present invention, the bucket or the carrying-out means may have a water supply hose connection portion for supplying water therein.

  In this embodiment, it has a water supply hose connection part, a water supply hose is connected, and water is supplied to the crushed soil. Thereby, when the crushed soil contains water and has a high viscosity and is difficult to be sucked, water can be supplied to the highly viscous soil to increase the water content and the viscosity can be reduced. As a result, interruption of the soil stripping and collecting operation can be reduced, the efficiency can be improved, and the continuity of the operation can be improved.

  [12] Preferably, the bucket of one embodiment applicable to the present invention may have an edge portion attached so as to protrude from the bucket.

  In this embodiment, the protruding edge portion is inserted into the contaminated soil by attaching the edge portion from the bucket so as to protrude substantially perpendicular to the soil surface, for example, and the depth inserted into the contaminated soil. The soil surface layer can be peeled off with such a precise thickness. Furthermore, by attaching an edge portion so as to protrude from the bucket to the soil surface, for example, approximately horizontally, the protruding edge portion reinforces the bucket, and the peeled soil surface layer is bucketed substantially horizontally with respect to the soil surface. Therefore, the stacking and unloading operations can be performed efficiently.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.

<< First Embodiment >>
<Schematic configuration of this embodiment>
In the first embodiment shown in FIG. 12 to FIG. 14, a normal backhoe-type detachable bucket 11 is attached to a hydraulic excavator 1 that is a self-propelled construction machine that can turn left and right and that has a vertically movable tip. This is the case. The hydraulic excavator 1 includes a main body 2 including a driver's seat portion that can be turned left and right, a chassis portion 3 that can be turned left and right by placing the main body 2 on top, a traveling portion 4 such as a crawler belt, and a hydraulic cylinder. And an arm portion 5 that can move up and down and back and forth.

  The excavator 1 is operated by an operator (including a case where the operator directly operates a self-propelled construction machine or the like, and a case where the operator performs remote operation. The same applies to the following “operating”). Drive to move forward, backward, turn right, turn left. The main body 2 can be turned left and right on the basis of the chassis 3 by an operator. One end of the U-shaped portion of the arm portion 5 is pivotally attached to the main body 2, and one end of the straight portion is pivotally attached to the other end of the U-shaped portion. Each of the U-shaped portion and the straight portion is equipped with a hydraulic cylinder, and the other end of the straight portion can be moved up and down by the hydraulic cylinder when operated by an operator. A bucket 11 is pivotally attached to the other end portion of the straight portion of the arm portion 5 which is a tip portion of the excavator 1 that can move up and down.

  The bucket 11 is attached to a vertically movable tip portion of a hydraulic excavator 1 that can turn left and right, and is used for stripping and collecting the soil surface layer 72. The bucket 11 operated the arm or the bucket back and forth with a mounting portion 12 having a pivoting portion with the other end of the straight portion of the arm portion 5 and a pivoting portion with a hydraulic cylinder arranged in parallel with the straight portion. In this case, a bucket opening 13 serving as an entrance for the soil that has been peeled off, a side plate 14 that is an upright plate that defines both side dimensions and both side surfaces of the bucket opening 13, and a bottom surface of the bucket opening 13 are defined. A bottom plate 15 that is a plate to be supported, and a back plate 16 that faces the bucket opening 13 of the bucket 11 and stands upright from the bottom plate 15. A bottom opening side end edge 17 is formed at the tip of the bottom plate 15 in the turning direction, and a bottom side end edge 18 is formed at both corners where the side plates 14 rise from the bottom plate 15. As an example of the bucket 11 having such a flat bottom surface and an edge, there is a slope bucket that has a wider bottom surface and is used for forming a slope in addition to a general bucket for a hydraulic excavator. .

<Soil surface layer peeling collection method of this embodiment>
The hydraulic excavator 1 shown in FIG. 12 is operated by an operator. First, in the region 73 where the soil surface layer 72 is removed, one end portion (region boundary portion) on the left and right sides with respect to the traveling direction of the hydraulic excavator 1. ) To the outer side of the front side of the removal start end 75 and stopped. In this case, one of the left and right ends may be arbitrary, but in the present embodiment, it is the right end with respect to the traveling direction of the excavator 1. Thus, in this embodiment, the removal starts from the right end (region boundary) in the region 73 to be removed.

  Next, by operating the operator, the bucket 11 is disposed at one of the left and right removal start ends 75 in the region 73 where the soil surface layer 72 is removed. In this case, one of the left and right ends may be arbitrary, but in this embodiment, since the removal starts from the right end, the bucket 11 is attached to the right end with respect to the traveling direction of the excavator 1. Deploy.

  Next, as shown in FIGS. 13A and 14A, the operator operates the bucket 11 disposed at the removal start end 75 to lower the removal start end 75. A flat bottom plate 15 constituting the bottom surface of the bucket 11 is grounded in parallel with the soil surface layer 72. In this case, the side plate 14 rises in the upright direction at the tip of the bottom plate 15 on the bottom surface in the turning direction. The bottom plate 15 and the side plate 14 form a bottom side edge 18 that extends in the direction perpendicular to the turning direction at the tip in the turning direction.

  FIG. 15 shows an embodiment of a bucket with an edge portion applicable to the present invention. The embodiment in which the edge portion is attached to the bucket is not limited to the embodiment shown in FIG. The left side view of FIG. 15A is a side view of the bucket 11 showing a state in which the edge portion 181 is attached so as to protrude from the bucket 11 substantially perpendicularly to the soil surface, and the right side view of FIG. FIG. 3 is a front view of the left side view as seen from the direction of the bucket opening 13 of the bucket 11.

  As shown in FIG. 15 (a), the plate-shaped edge portion 181 is fixed to the side plate 14 of the bucket 11 so as to protrude from the bottom surface side end edge 18 of the bucket 11 substantially perpendicularly to the soil surface. 200 and the nut 210 are detachably attached. By attaching the edge portion 181 protruding from the bucket 11, the protruding edge portion 181 is inserted and disposed in the contaminated soil. By swinging the bucket 11 left and right like a wiper in the horizontal direction in parallel with the soil surface, the edge portion 181 can peel the soil surface layer with an accurate thickness by the depth inserted into the contaminated soil. . Thus, by providing the edge part which protruded from the bucket 11, the thickness of the soil surface layer to peel off can be controlled correctly. For example, when the thickness of the soil surface layer to be peeled is set to 3 cm, the edge 181 is detachably attached to the side plate 14 with the fixing bolt 200 and the nut 210 so that the protruding width D1 ″ of the edge 181 is 3 cm. By fixing, it becomes easy to accurately control the thickness of the soil surface layer to be peeled off to 3 cm. The method for attaching the edge portion is not limited to the method using the fixing bolt and nut, and the edge portion may be attached to the side end portion of the bucket 11 by other methods. The protruding width D1 ″ of the edge portion 181 can be set according to the thickness of the soil surface layer to be peeled off. When the thickness of the soil surface layer to be stripped is 10 cm, the plate-like edge What is necessary is just to fix to the side plate 14 of the bucket 11 so that protrusion width D1 '' of the part 181 may be 9-10 cm. When the thickness of the soil surface layer to be peeled off is 5 cm, it may be fixed to the side plate 14 of the bucket 11 so that the protruding width D1 ″ of the plate-like edge portion 181 is 3 to 5 cm. When the thickness is 4 cm, the plate-like edge portion 181 may be fixed to the side plate 14 of the bucket 11 so that the protruding width D1 ″ is 3 to 4 cm.

  In FIG. 15B, a plate-like first edge portion 182 is attached so as to protrude from the bucket 11 substantially perpendicular to the soil surface, and the plate is projected from the bucket 11 substantially horizontally to the soil surface. It is a side view of the bucket 11 which shows the state which attached the 2nd edge part 183 of shape, and the right view is the front view which looked at the left side view of FIG.

  As shown in FIG. 15B, the plate-like first edge portion 182 protrudes from the bottom surface side edge 18 of the bucket 11 substantially perpendicular to the soil surface, and also protrudes from the back plate 16 of the bucket 11. It is detachably attached to the side plate 14 of the bucket 11 by a fixing bolt 200 and a nut 210 so as to project the length L1. Further, the plate-like second edge portion 183 is attached to the bottom plate 15 of the bucket 11 so as to protrude substantially horizontally from the bottom surface opening side end edge 17 of the bucket 11. By attaching the plate-like first edge portion 182 so as to protrude from the bottom surface side edge portion edge 18 of the bucket 11 substantially perpendicularly to the soil surface, the protruding first edge portion 182 and second edge portion 182 are attached. An edge portion 183 is inserted and disposed in the contaminated soil. The depth at which the first edge portion 182 is inserted into the contaminated soil when the bucket 11 is swung left and right like a wiper in the horizontal direction in parallel with the soil surface (the protruding width of the first edge portion 182) The soil surface can be stripped with an accurate thickness by D1 ″). Further, since the first edge portion 182 protrudes from the back plate 16 of the bucket 11 by the protruding length L1, it is possible to peel a wide range of contaminated soil surface layer. Further, the second edge portion 183 is attached so as to protrude substantially horizontally from the bottom surface opening side edge 17 to the soil surface, so that the nail-like bottom surface opening side end attached to the bucket opening 13 is provided. The part edge 17 can be reinforced. Furthermore, since the second edge portion 183 protrudes substantially horizontally with respect to the soil surface from the bottom opening side end edge 17, the soil surface layer peeled off at the protruding portion is scooped up, and the second edge portion 183 It is possible to deposit and remove the peeled soil surface efficiently. The second edge portion 183 may be attached to the bottom plate 15 of the bucket 11 by welding, or may be detachably attached to the bottom plate 15 of the bucket 11 with a fixing bolt, a nut, or the like.

  FIG.15 (c) is a side view of the bucket 11 which shows the state which attached the two plate-shaped edge parts 181 and 181 so that it protrudes substantially perpendicularly with respect to the soil surface on both sides of the bucket 11, and it is a right view. FIG. 15C is a front view of the left side view of FIG. 15C viewed from the direction of the bucket opening 13 of the bucket 11.

  As shown in FIG. 15C, the two plate-like edge portions 181 are attached to the side plates 14 on both sides of the bucket 11 by fixing bolts 200 and nuts 210, respectively. Two edge portions 181 protruding from both sides of the bucket 11 are inserted and arranged in the contaminated soil. The two edge portions 181 can more precisely control the thickness of the soil surface layer that the one edge portion 181 reinforces and peels off the other edge portion 181.

  Next, the bucket 11 grounded to the removal start end 75 is operated in the left turn direction among the directions in which the main body 2 can turn left and right while being grounded to the soil surface layer 72 by the operator. It is turned. When the bucket 11 is turned in the left turning direction, the soil 61 that has started to be peeled off from the soil surface layer 72 is removed from the bottom side edge 18 as shown in FIGS. 13 (a) and 14 (a). It accumulates outside in the direction of travel and is carried in the direction of travel. Further, as the bucket 11 is turned in the left turn direction, as shown in FIGS. 13 (b), 14 (b) and (c), more soil 62 peeled off from the soil surface layer 72 is removed. Then, it accumulates outside the bottom edge 18 and is pushed in the direction of travel. The area 19 where the soil 62 peeled off from the soil surface layer 72 by the bottom side edge 18 in FIG. 14B at that time is enlarged and shown in FIG.

  In the final stage of turning of the bucket 11 in the left turning direction, as shown in FIGS. 13C and 14D, the bucket 11 is turned from the soil surface layer 72 by turning the bucket 11 in the left turning direction once. All the stripped soil 63 accumulates outside the bottom side edge 18 and is pushed in the direction of travel. Eventually, when all of the stripped soil 63 reaches the removal end edge 76, it is fused with the streak-removed bank 65 formed by the previous removal work, and a new streak-removed bank 65 is formed. It is formed.

  The streak-removed embankment 65 can be collected by, for example, a general loader discharge plate or scooped up by a hydraulic excavator and dropped and accumulated on a loading platform of a transport vehicle such as a dump truck. However, once the streak-removed embankment 65 is accumulated or carried out, the stripping thickness is easy to strip, and the stripping thickness cannot be reduced, so that a wasteful amount of stripping / scraping is generated. Also, for example, in the case of contaminated soil, there is a possibility that the contamination may expand due to overloading by moving the soil, so it is not preferable to collect and carry out with a soil discharging plate or a hydraulic excavator There is.

When the work of collecting and unloading with such a soil discharging plate or a hydraulic excavator is not preferable, for example, soil removed by a suction hose connected to a vacuum suction device (vacuum pump or vacuum car) as unloading means. As soon as a part of the streak-removed embankment 65 is formed, it is possible to reduce the work man-hours during soil accumulation and unloading, and to eliminate spillage. The suction capacity must be at least capable of sucking and collecting mud, semi-solid or solid, and should be selected in consideration of the area to be stripped off, the location, and the like. As an example, one having a capacity of about a theoretical air volume of 12 to 100 m ³ / min can be used.

  Further, in order to more reliably and stably peel off the soil surface layer 72, a soil solidifying slurry material containing a solidifying agent and a liquid is sprayed on the region 73 where the soil surface layer 72 is removed, and permeates only the surface layer. By doing so, the soil in the region 73 can be solidified. The slurry material for solidifying the soil in this case may be blended with a blending ratio of the solidifying agent and the liquid (solidifying agent: liquid) at a ratio of, for example, 1: 3-4, and sprayed with the generator to improve workability. It may be sprayed with palpitations using a machine.

  Further, by using the soil solidifying slurry material, the soil surface layer 72 of the region 73 to be removed is hardened with a composition different from that of the underlying soil. The efficiency is improved, the dust winding is reduced, and a safe and reliable removal operation is possible. Further, since the separation at the boundary portion is facilitated, the stripping operation is facilitated. Moreover, as a solidifying agent used for the slurry material for soil solidification, for example, when a magnesia-based solidifying agent is used, the solidified soil can be changed to, for example, white so that it can be visually confirmed. While checking the solidified soil part visually, the soil surface layer including the solidified soil part is peeled off, and the area where the stripping work has been completed and the unworked area can be easily distinguished by visual recognition, facilitating construction management. be able to.

  Thus, according to the stripping and collecting method of the soil surface layer 72 of this embodiment, the bucket 11 is grounded to one of the left and right removal start ends 75 in the region 73 where the soil surface layer 72 is removed, and the bucket 11 is In a state where the soil surface layer 72 is grounded, the left and right turning motion of the excavator 1 is used to swivel in one of the directions in which the left and right can be turned, thereby peeling off the soil surface layer 72 in the lateral direction. This operation is performed by temporarily stopping the hydraulic excavator 1 at the peeling position and turning only the bucket 11 in the lateral direction in a stable state.

  Therefore, compared to the case where the soil is peeled off while being self-propelled as in the conventional case, and the case where the operator operates the bucket 11 in the self-propelled direction (or the direction opposite to the self-propelled direction) and peels the soil. It can reduce that the bucket 11 goes too deeply into the layer to be peeled off during the taking. As a result, the soil to be peeled can be thinly stabilized only on the surface layer of 2 to 3 cm, for example. Further, since the operation of turning only the bucket 11 in the horizontal direction is an operation that has been conventionally performed when leveling the soil with the hydraulic excavator 1, the operation can be performed relatively easily. Since the state of the soil surface layer 72 into which the bottom end edge 18 of 11 is inserted can be visually confirmed, it can be carried out reliably.

  In the present embodiment, the bottom surface of the bucket 11 is a flat bottom plate 15 and the plane is grounded. As a result, when the bucket 11 is swung while being grounded to the soil surface layer 72, the front end side of the bottom plate 15 in the traveling direction of the swirl becomes the bottom-side end edge 18 perpendicular to the swiveling direction, and the bottom side The soil surface layer 72 can be peeled off at the end edge 18. Moreover, the bottom plate 15 that is a flat surface can stabilize the bottom end edge 18 of the bucket 11 so as not to be inserted too much into the soil surface layer 72, and can prevent the bucket 11 from sinking excessively. . Therefore, the soil surface layer 72 can be thinly and stably peeled off. Moreover, since it has the side plate 14 arrange | positioned from the bottom plate 15 in the upright direction, the soil peeled off by the upright side plate 14 can be pushed and conveyed in the advancing direction.

<< Second Embodiment >>
<Features of schematic configuration of the present embodiment>
In the first embodiment described above, the soil surface layer is obtained by turning the excavator 1 left and right using the bottom side edge 18 between the bottom plate 15 and the side plate 14 of the bucket 11 used in a normal backhoe or the like. 72 was peeled off at the bottom side edge 18 and the soil 61 to 63 was pushed in the traveling direction by the side plate 14. However, when carrying the soil with the side plate 14, if the amount of soil increases, the amount of soil spilling from the left and right of the side plate 14 increases. Therefore, in the soil surface peeling and collecting method according to the second embodiment shown in FIG. 16, the bucket 21 is formed in a direction in which the bucket opening 23 is turned.

  The bucket 21 has an attachment portion 22 having a pivot portion with the other end of the straight portion of the arm portion 5 and a pivot portion with a hydraulic cylinder arranged in parallel with the straight portion, and an entrance into which the peeled soil enters. A bucket opening 23, a side plate 24 that is an upright plate that defines both side surfaces of the bucket opening 23, a bottom plate 25 that is a plate that defines the bottom surface of the bucket opening 23, and a bucket opening of the bucket 21 23 and a back plate 26 standing upright from the bottom plate 25.

  The bucket opening 23 is oriented in the turning direction, the bottom plate 25 is formed in a plane parallel to the surface layer of the soil, and the bottom opening side end edge 27 orthogonal to the turning direction is formed at the tip of the bottom plate 25 in the turning direction. At both corners where the both side plates 24 are formed from the bottom plate 25, bottom end edges 28 are formed. For peeling off the soil surface layer 72, the bottom opening side end edge at the tip in the turning direction is used, and as the bucket 21 is turned, the peeled soil is guided directly from the bucket opening 23 to the inside of the bucket 21. The Other configurations are the same as those of the first embodiment.

<Characteristics of stripping and collecting method of soil surface layer of this embodiment>
In this embodiment, when the bucket 21 is swung, the bucket opening 23 is directed in the swirling direction, and the soil peeled off from the soil surface layer 72 is guided into the bucket 21 and stopped by the back plate. Therefore, until the capacity of the bucket 21 is full, the peeled soil does not spill. As a result, the amount by which the peeled soil is pushed in the traveling direction can be increased, and the amount spilled from the front surface of the bucket 21 can be reduced. Other construction methods are the same as those in the first embodiment.

<< Third Embodiment >>
<Features of schematic configuration of the present embodiment>
In the second embodiment described above, by turning the bucket opening 23 of the bucket 21 in the direction of turning, the amount of spilled soil is reduced, and the amount of pushed-off soil is increased in the traveling direction. However, as in the first embodiment, the soil that has entered the bucket 21 needs to be temporarily accumulated as the streak-removed embankment 65 or dropped onto the loading platform of a transport vehicle such as a dump truck and accumulated. Yes, the efficiency of the collection and unloading work was not improved. Accordingly, in the third embodiment shown in FIGS. 17 to 19, the efficiency of the work of stacking and unloading by connecting a suction hose directly to the bucket 31 as unloading means is improved.

  The basic configuration of the bucket 31 itself is the same as that of the second embodiment, and the bucket 31 is pivotally connected to the other end of the straight portion of the arm portion 5 and a hydraulic cylinder arranged in parallel with the straight portion. A mounting portion 32 having a landing portion, a bucket opening 33 serving as an entrance for the stripped soil, a side plate 34 that is an upright plate defining both side surfaces of the bucket opening 33, and a bucket opening 33 A bottom plate 35 that defines the bottom surface of the bucket 31 and a back plate 36 that faces the bucket opening 33 of the bucket 31 and stands upright from the bottom plate 35.

  The bucket opening 33 is directed in the turning direction, the bottom plate 35 is formed in a plane parallel to the surface layer of the soil, and the bottom opening side end edge 37 perpendicular to the turning direction is formed at the tip of the bottom plate 35 in the turning direction. At both corners where both side plates 34 are formed from the bottom plate 35, bottom end edges 38 are formed. Since the bottom surface opening side end edge 37 at the tip in the turning direction is used for peeling off the soil surface layer 72, the peeled soil is directly moved from the bucket opening 33 to the inside of the bucket 31 as the bucket 31 is turned. Be guided.

  In addition to the same configuration as that of the second embodiment described above, in this embodiment, the bucket 31 has a suction opening 86 in the back plate 36. Further, the suction opening 86 is formed so that a suction hose 88 connected to the vacuum suction device 92 can be connected via the soil recovery container 91. Although not shown, the soil collection container 91 and the vacuum suction device 92 may be integrated without being connected by the suction hose 88. By integrating the soil collection container 91 and the vacuum suction device 92, the suction force becomes strong, and the soil surface layer peeled off from the bucket 31 to the soil collection container 91 can be accumulated.

  One end of the suction hose 88 is connected to a vacuum suction device 92 such as a vacuum pump or a vacuum car, and the other end of the suction hose 88 is connected to the bucket 31. The soil guided into the bucket 31 as described above is sucked and discharged as it is from the bucket 31 into the suction hose 88 without delay, and moves through the suction hose 88 and is conveyed to the soil collection container 91. The In the soil collection container 91, the soil and air are separated by the dead weight of the soil or by a cyclone method, and only the internal air is further discharged to the vacuum suction device 92 through the suction hose 88. With this configuration, in the present embodiment, when the bucket 31 is swung, the soil guided into the bucket 31 from the bucket opening 33 is immediately transferred to the soil collection container 91 via the suction hose 88. Accumulated.

  Therefore, when the soil is once accumulated like the streak-removed embankment 65 on the side portion in the traveling direction of the hydraulic excavator 1 as in the above-described embodiment, Compared to the case where the peeled soil guided inside is dropped and accumulated every time on the loading platform of the transport vehicle, the amount of the soil removed from the front of the bucket 31 is further reduced. be able to. Therefore, it is possible to eliminate or reduce the process of collecting and transporting the peeled soil from the accumulation site. As a result, the time for interrupting the stripping collection of the soil surface layer 72 and the accompanying work can be reduced, and the continuity of the stripping collection of the soil surface layer 72 can be enhanced. As a result, it is possible to improve efficiency by reducing time and man-hours, and it is possible to make the work safe because an operator working in the vicinity of the self-propelled construction machine at the time of stacking and transportation is not necessary.

  Further, in the bucket 31 of the present embodiment, a crushing device 80 that crushes plant bodies such as soil and weeds peeled from the soil surface layer 72 and plant residues such as rice stock and rice straw in the vicinity of the bucket opening 33. Is provided. Thus, when the bucket 31 is swung, the soil crushed by the crushing device 80 is guided into the bucket 31 and accumulated in the soil collection container 91 via the suction hose 88.

  The crushing device 80 includes a rotating shaft 81 to which a plurality of breaking blades 82 are attached, and a motor 84 that drives the rotating shaft 81 at a speed faster than a speed at which the peeled soil is guided. When crushing plant bodies such as stripped soil and weeds, plant residues such as rice stocks and rice straw, etc., the rotating shaft rotates at a speed sufficiently faster than the speed at which the soil stripped by turning is induced. It is carried out. For example, the speed at which the surface of the rotating shaft 81 rotates in the circumferential direction is set to be several times the speed at which the soil is introduced into the bucket 31. As the blade 82, for example, a hammer knife type blade used for mowing mowers of agricultural machinery can be used, so that plant bodies and plant residues can be efficiently crushed.

  Since the crushing device 80 is provided in the bucket 31 and the suction hose 88 is connected, the peeled-off soil can be crushed and sucked, so that the water content is large or clayey or the like naturally or intentionally. Even when the soil is peeled off, the soil can be crushed continuously. As a result, the soil stays in the suction hose 88 and the suction efficiency is lowered. Further, the suction hose 88 is clogged and the suction efficiency of the soil is lowered or cannot be sucked. Stopping the collection operation can be reduced, improving the efficiency of the soil removal collection operation, reducing the interruption for maintenance of the suction hose 88, and reducing the continuity of the collection operation. Can be improved. Further, by reducing the amount of soil retained in the bucket 31 and suppressing the increase in weight, the bucket 31 can be prevented from entering too deeply into the layer to be peeled off during peeling. In addition to the suction hose, the carry-out means is, for example, a softness formed by inserting a flexible screw such as a polymer material into a tube formed of a flexible material such as a polymer. Can be used. The screw may be shaftless.

(Application 1 of the third embodiment)
Further, in the vicinity of the suction opening 86 of the bucket 31 or in the vicinity of the connection portion to the suction opening 86 of the suction hose 88, there is a water supply hose connection portion (not shown) for supplying water into the portion, A hose can be connected. Thereby, water can be supplied to the crushed soil in the vicinity of the suction opening 86 or in the suction hose 88.

  In this application example, a water supply hose is connected to the water supply hose connecting portion, and water is supplied to the crushed soil. As a result, when the crushed soil contains water and is highly viscous and difficult to suck, the water content is increased by further supplying water from the water supply hose to the highly viscous soil, thereby reducing the viscosity. Can be made. By reducing the viscosity of the soil with this water supply, the soil stays in the suction hose and the suction efficiency decreases, and the suction hose becomes clogged and the soil cannot be sucked. Stopping the stripping and collecting work can be reduced. As a result, interruption of the soil stripping and collecting work for maintenance of the suction hose can be reduced, the efficiency can be improved, and the continuity of the work can be improved.

(Application 2 of the third embodiment)
A screw conveyor that can guide the crushed soil to the suction opening 86 without delay can be provided in the bucket 31. The screw conveyor is arranged in a direction for guiding the crushed soil to the suction opening 86 and is driven by a motor. As a result, the amount of crushed soil remaining in the bucket 31 can be reduced, so that the soil peeled off in the bucket 31 can easily enter, and the resistance to the stripping and collecting work on the soil surface layer 72 is reduced. The work efficiency can be improved.

  Thus, according to the peeling collection method and bucket of the soil surface layer 72 of each embodiment described above, the angle at which the edge portion protruding from the bottom surface side edge or the side edge of the bucket is inserted into the soil surface increases. Therefore, the thickness of the soil surface layer to be removed can be stabilized within the thin range of the soil surface layer. Moreover, the operator can visually recognize the extent to which the side edge of the bottom surface of the bucket or the edge protruding from the side edge of the bucket has been inserted into the soil surface layer of the removal region. Furthermore, the operator's operation can be an easy task of turning left and right, and the difficulty of operation can be suppressed.

  In each of the above embodiments, the case of removing the soil surface layer on a flat ground has been described. However, the soil surface layer stripping collection method and bucket applicable to the present invention are not limited to this, for example, a slope or a hilly soil. Even when the surface layer is peeled off and collected, for example, the excavator 1 can be arranged on the upper side of the slope, and the arm unit 5 can be swung on the lower side and the swiveling direction can be adjusted. Moreover, in the said construction method, the buried seed buried in the surface soil can be efficiently collected, and the soil can be separated into several centimeters according to the purpose.

  The method for removing a contaminated soil surface layer of the present invention can be suitably used for removing a contaminated soil surface layer in a field such as paddy field soil. When the target soil is paddy soil, it is preferable to spray the soil solidifying slurry material after drying the paddy soil to some extent. After the paddy soil is dried to some extent, the soil-solidifying slurry material containing the solidifying agent and the liquid is likely to penetrate, and the contaminated soil surface layer is easily stripped to a thickness intended for removal. In addition, when the target soil is paddy soil, it is preferable to remove weeds and the like in the target soil before spraying the soil-solidifying slurry.

  Hereinafter, the present invention will be described in more detail by way of examples. The present invention is not limited to these examples.

(Examples 1-4)
From July 6, 2011 to July 15, 2011, the following test was conducted in Iitate Village, Fukushima Prefecture.
The radiation dose in the atmosphere (before treatment) at a height of 5 cm from the soil (1 m ² ) of the paddy soil was previously measured by Mr. Gamma (manufactured by Clear Pulse). The results are shown in Table 1 (the unit of radiation dose in Table 1 is microsievert per hour (μSv / h)). (1) A magnesia-based solidifying agent shown below is mixed with water at a blending ratio shown in Table 1 to form a slurry-like soil-solidifying slurry material, and this soil-solidifying slurry material A1 is dropped by rain dew B1, and the test area It spread | dispersed on the soil surface C1 (1m < ² >) used. In addition, content of magnesium oxide in 100 mass% of magnesia type solidifying agents shown below is 15-55 mass%. The application amount of the soil solidifying slurry was 2 kg / m ² (solid content). FIG. 2 is a photograph showing a state in which the soil solidifying slurry A1 is sprayed on the soil surface C1 (1 m ² ) serving as a test area with rain dew B1.
Magnesia solidifying agent: Mag White III type (MgWIII), Blaine specific surface area 6,000 cm ² / g, Tobu Chemical Co., Ltd. Magnesia solidifying agent: Mag White III P type (MgWIIIP), Blaine specific surface area 8,000 cm ² / g, Tobu Chemical Co., Ltd.

(2) After spraying slurry-like soil solidifying slurry material A1 containing magnesia-based solidifying agent on soil surface C1, curing is performed for 9 days, and magnesia-based solidifying agent is infiltrated into the soil, depth 1 to depth from soil surface C1. The soil part within 3 cm was solidified. The soil surface layer D1 including the solidified soil portion turned white and could be visually recognized.

(3) The soil surface layer D1 including the solidified soil portion was manually peeled off using a scoop E1. FIG. 3 is a photograph showing a stripping state of the soil surface layer D1 including the solidified soil portion. The soil surface C1 'after peeling off the soil surface layer D1 was not whitened and could be visually confirmed. FIG. 4 is a photograph showing a situation in which the thickness of the soil surface layer D1 including the solidified soil portion D1 'peeled off is measured. As shown in FIG. 4, the thickness of the soil surface layer D1 including the solidified soil portion D1 'peeled off was about 2 to 3 cm.

  The radiation dose in the atmosphere at a height of 5 cm from the soil surface C1 'after peeling off the soil surface layer was measured by Mr. Gamma (manufactured by Clear Pulse). FIG. 5 is a photograph showing a situation in which the radiation dose in the atmosphere at a height of 5 cm from the soil surface C1 'after peeling off the soil surface layer is measured. Table 1 shows the measurement results of the radiation dose (after peeling off the soil surface layer). Furthermore, the radiation dose (treated soil) in the atmosphere at a height of 5 cm from the soil surface where the soil surface layer D1 including the solidified soil portion D1 'peeled off was deposited was measured. Table 1 shows the measurement results of radiation dose.

[Consideration of the results of Examples 1 to 4]
As shown in Table 1, the paddy soil to which the contaminated soil surface removal method of the present invention is applied has a reduced radiation dose in the atmosphere before enforcement and after stripping the contaminated soil surface layer D1. It was confirmed that by removing the contaminated soil surface layer D1 by the method of the invention, the radiation dose in the area contaminated by the radioactive material can be reduced. In Iitate Village, Fukushima Prefecture, where the test was conducted, the radiation dose in the atmosphere around the tested soil was high, so the effect of stripping the soil surface was difficult to understand. After (after construction), as shown in Table 1, the radiation dose is clearly reduced. Furthermore, the thickness of the contaminated soil surface peeled off by the construction of the present invention is about 2 to 3 cm, and from this, only the soil surface within a depth of about 2 to 3 cm from the soil surface where the contaminants remain can be quickly and It was confirmed that it was possible to remove the soil as much as possible, to reduce the construction cost, and to reduce the burden after the treatment. In Examples 1 to 3, a solidifying agent (MgWIIIP: Blaine specific surface area 8,000 cm ² / g) having a large Blaine specific surface area is used. In Example 2, the soil surface layer is solidified. It was confirmed by visual observation that the solidifying agent was floating on the soil surface and the solidifying agent was difficult to penetrate into the soil.

(Example 5)
From July 21, 2011 to July 29, 2011, the following tests were conducted at a field test site in the Institute of Rural Engineering, Ibaraki Prefecture.
The surface (225 m ² ) of paddy soil (hereinafter referred to as “test soil”) in the field to be the test area is divided into a grid of 5 m in length and width, and the atmosphere at a height of 5 cm from the soil surface at the intersection of 5 m in length and width. The radiation dose (before treatment) was measured by TCS-161 (manufactured by Hitachi Aloka Medical). The results are shown in Table 2 (the unit of numerical values in Table 2 is microsievert per hour (μSv / h)). (1) A magnesia-based solidifying agent (Mug White IIIP type (MgWIIIP)) is mixed with water to form a slurry-like solidifying slurry A2 (solidifying agent: water ratio (solidifying agent: water = 100 parts by mass: 300 parts by mass). Part)). FIG. 6 is a photograph showing a sprayer B2 for spraying the soil solidifying slurry A2 used in the present example to the soil surface and a generator B2 ′ for driving the sprayer B2. FIG. 7 is a photograph showing a state in which slurry-like soil solidifying slurry material A2 is sprayed evenly onto test soil surface C2 (225 m ² ) by spraying machine B2. The application amount of the soil solidifying slurry A2 was 2 kg / m ² (solid content).

(2) After dispersing slurry-like soil solidifying slurry A2 containing a solidifying agent on soil surface C2, it is cured for 6 to 7 days, the solidifying agent is permeated into the soil, and within 1 to 3 cm in depth from soil surface C2. The soil part of was solidified.

(3) Use a hydraulic excavator, which is a self-propelled construction machine, and swing the bucket parallel to the soil surface by swiveling the bucket, which is the working part, to the left and right within the range of the caterpillar width of the hydraulic excavator. That is, the soil surface layer D2 including the solidified soil portion D2 ′ was peeled off by swinging the bucket to the left and right like a wiper in the horizontal direction in parallel with the soil surface. The thickness of the soil surface layer including the solidified soil portion D2 'thus peeled off was about 2 to 3 cm. 8 to 11 are photographs showing a state in which the thickness of the soil surface layer D2 including the solidified soil portion D2 'peeled off from different parts of the test soil is measured. The peeled soil surface layer was collected in an area after being deposited in an area where the sliding of the bucket stopped.

The radiation dose of the test soil surface (225 m ²⁾ from the intersection portion is divided by horizontal and vertical 5m is divided in a grid pattern by vertical and horizontal 5m height 5cm atmosphere after peeled surface soil D2 TCS-161 (Hitachi Aloka (Manufactured by Medical). The results are shown in Table 3 (the unit of numerical values in Table 3 is microsievert per hour (μSv / h)).

[Consideration of the results of Example 5]
As shown in Tables 2 and 3, the soil in which the construction method of the present invention was constructed had a reduced radiation dose before enforcement (Table 2) and after the soil surface was stripped (Table 3). Even if the area where the construction method of the invention is applied is wide (test soil surface 225 m ² ), the radiation dose in the test soil area is evenly reduced, so that contaminants can be reliably removed without partial loss. It could be confirmed. In Example 5, it took about 2.5 hours for the soil surface layer to be peeled off, including loading on a large sandbag (for flexible container bag 1t). The soil surface layer was quickly stripped and contaminated. It was confirmed that the substance could be removed reliably.

  Moreover, as shown to FIGS. 8-11, the thickness of the peeled soil surface layer is about 2-3 cm, the amount of soil to remove can be reduced as much as possible, construction cost can be reduced, processing It was confirmed that the subsequent burden could be reduced. Furthermore, during the construction, the generation of dust was suppressed, and it was confirmed that the contaminants were prevented from being scattered with the generation of the dust, thereby ensuring the safety of the installer.

  The method for removing a contaminated soil surface layer according to the present invention is a method for quickly and rapidly removing a contaminated soil surface layer containing contaminants that remain in the surface layer within a depth of about 5 cm from the soil surface due to heavy metals contained in irrigation water or radioactive materials in the atmosphere. It is possible to remove the waste as much as possible at a lower cost to reduce the processing burden after the removal treatment, and to physically remove it so that the safety of the installer is ensured. The area where the numerical value is higher than the standard value due to heavy metals such as cadmium and copper and harmful substances such as arsenic is about 7,500 hectares (ha). In addition, due to the accident at the nuclear power plant, the area of farmland contaminated with radioactive materials is about 10,000 hectares (about 7,000 houses), and the cultivation of rice in soil with more than 5000 becquerels / kg of radioactive material is present. Is limited. The method for removing a contaminated soil surface layer according to the present invention can be used for restoration of a disaster-stricken area as a method for removing a contaminated soil surface layer that has been extensively contaminated by radioactive substances or the like, and is very useful industrially.

A1, A2 Soil solidifying slurry material B1 Rain dew B2 Spraying machine B2 'Generator C1, C2 Soil surface for testing C1' Soil surface after stripping D1, D2 Soil surface layer D1 ', D2' Solidified soil part 1 Hydraulic excavator ,
2 body,
3 chassis,
4 running section,
5 Arm part,
11, 21, 31 bucket,
12, 22, 32 mounting part,
13, 23, 33 Bucket opening,
14, 24, 34 side plate,
15, 25, 35 Bottom plate,
16, 26, 36 Backboard,
17, 27, 37 Bottom opening side end edge,
18, 28, 38 Bottom side edge,
19 areas,
61 Soil (beginning to peel off)
62 (more) soil,
63 (All) soil,
65 Streak removal,
72 soil surface,
73 region (to be removed),
75 removal start end,
76 End of removal end,
80 crusher,
81 rotation axis,
82 blades,
84 motor,
86 Suction opening,
88 Suction hose (unloading means),
91 soil collection container,
92 vacuum suction device,
181, 182, 183 edge,
200 fixing bolts,
210 Nut.

Claims (10)

A step of placing a bucket attached to a self-propelled construction machine capable of turning right and left in a region where the soil surface layer is removed, a step of grounding the bucket to the soil surface layer, and grounding the bucket to the soil surface layer And turning in the left and right turnable direction,
In the bucket, the bucket opening is directed in the direction in which the bucket is swung, the plate in the upright direction is a back plate, and at least the carry-out means extended to the soil collection container is connected. The soil peeled off from the bucket opening is guided into the bucket, and the soil of the bucket is accumulated in the soil collection container via the carrying-out means,
A method for stripping and collecting soil surface layers.   The bucket has a flat bottom surface, an edge is formed at a tip of the bottom surface in the turning direction, the bottom surface has at least one plate in an upright direction, and in the step of grounding the bucket, the bottom surface is The method for stripping and collecting the soil surface layer according to claim 1, wherein the soil surface layer is grounded. The method for stripping and collecting a soil surface layer according to claim 1 or 2 , wherein the bucket is provided with a crushing device for crushing the soil, and in the turning step, the crushed soil is guided into the bucket. The soil crushing and collecting method according to claim 3 , wherein the crushing device is configured by attaching a plurality of blades to a motor-driven rotating shaft, and the crushing is performed by rotating the rotating shaft. . Wherein the bucket or the carrying-out means, the water supply hose is connected to water supply to the internal and supplying water to the soil, stripping collection method of soil surface of any of claims 1-4.   A bucket attached to a self-propelled construction machine capable of turning left and right, wherein the bucket is formed in a flat surface and has a bottom surface formed with an edge at a tip in the turning direction, a bucket opening directed in the turning direction, and A suction opening provided in a back plate formed in an upright direction from the bottom surface, and a crushing device for crushing the soil peeled off from the soil surface layer, and the suction opening is connected to a carrying means A bucket that is shaped to be able to. The bucket according to claim 6 , wherein the crushing device includes a rotating shaft to which a plurality of blades are attached, and a motor that drives the rotating shaft. The bucket according to claim 6 or 7 , wherein the crushing device further includes a screw conveyor for guiding the crushed soil to the suction opening. The bucket according to any one of claims 6 to 8 , wherein the bucket or the carry-out means has a water supply hose connection part for supplying water therein. The bucket according to any one of claims 6 to 9 , further comprising an edge portion attached so as to protrude from the bucket.