JP4535821B2 - Soft soil improvement method and solidifying material filling apparatus used therefor - Google Patents

Description

  The present invention, for example, mixes soft soil such as peat, highly hydrous viscous soil, weathered volcanic ash with a solidifying material, and solidifies the solidifying material with moisture in the soft soil to improve the strength of the soft soil. And a device used for the method.

  Soft soil (hereinafter referred to as “soft soil” in the description of the present invention) such as peat, highly hydrous viscous soil, weathered volcanic ash, dredged soil, and construction generated soil cannot be used as it is, and the ground for the surface layer. In the case of improvement work or construction civil engineering work, it has been disposed of. However, the effective use of resources has attracted attention for the purpose of building a recycling-oriented society, and if soft soil that has been disposed of is improved, it can be used without being disposed of.

As one of the methods for improving soft soil, there is a method of improving by mixing solidifying materials such as cement and lime. As solidification materials, for example, cement-based solidification materials, cement-lime-based solidification materials, and gypsum-based solidification materials described in Patent Documents 1 to 3 are known. Currently, when mixing solidified materials such as cement and lime with soft soil, break the bags containing the solidified material from above and spray them with a hose. I do. After spraying, the solidified material and soft soil are mixed using an appropriate stirring and mixing device.
JP 2002-137950 A JP 2002-294232 A JP 2002-363558 A

The following problems can be pointed out in the prior art.
Since the solidified material is in the form of powder and the solidified material does not contain moisture, the solidified material scatters around in a large range when sprayed. Especially when there is wind, it is scattered over a wide area. Such scattering also occurs at the initial stage of stirring and mixing performed after spraying. It is unfavorable from the viewpoint of the environment and the health of the worker that the dust of the solidifying material is scattered to an unnecessary range. Moreover, it also becomes a loss of solidification material. As a method for preventing scattering when the solidifying material is sprayed, the construction site is surrounded by a high fence, or a person who works directly wears a dust mask.

  However, when it is enclosed by a fence or the like, the equipment and installation work are costly. Moreover, wearing a dust mask is troublesome, workability is reduced, and loss due to scattering of the solidified material is inevitable. In addition, there is a machine that performs stirring and mixing in a completely sealed state, but it is a large-scale device and is expensive.

  In view of the above situation, the present invention is a method and an apparatus used for improving soft soil by mixing it with a solidifying material, and prevents the scattering of the solidifying material and at low cost without losing the solidifying material. It is aimed to be able to mix uniformly and efficiently.

In order to solve the above-described problems, the present invention is as follows.
In the present invention, for example, a powdery solidified material (cement, lime, coal ash, etc.) is filled in a soft soil such as peat, highly hydrous viscous soil, weathered volcanic ash, and then stirred with the surrounding soft soil. Thus, a method of mixing soft soil and solidified material uniformly without scattering the solidified material and improving the soft soil with solidification of the solidified material is provided as a basic principle, and an apparatus capable of carrying out this method is provided.

(1) soft soil improvement method according to claim 1, powdery in a method of solidifying material are mixed to improve the soft soil by solidifying, powdered solidified into the press can be cylindrical body in the deposited soft soil the closable outlet provided at the lower end of the tubular member so as to release the openable inlet opening state Toshikatsu tubular body of powdered solidifying material for introducing the timber to a closed state After the input port and the discharge port are interlocked , the powdered solidified material is input into the cylindrical body from the input port, and the cylindrical body is press-fitted into the accumulated soft soil. a step of providing a cylindrical hole extending vertically downward from the soft soil surface, the inlet of the cylindrical body and a-projecting inlet and outlet aperture to the outlet in the closed state Toshikatsu the cylindrical body to the open state after interlocked, Hikiageruko the tube body while releasing the powdery solidification agent from outlet aperture By and having a step of stirring and mixing with the columnar and filling the powder-like solidifying material in the bore, the deposited is the filling of soft soil was a powdery solidifying material.

( 2 ) The solidifying material filling apparatus according to claim 2 is the solidifying material filling apparatus used in the soft soil improvement method according to claim 1 , and has the cylindrical body, and is press-fitted into the accumulated soft soil. And a discharge valve that is attachable to a driving device for lifting, and is provided at the lower end portion of the cylinder so as to be movable up and down relative to the cylinder in order to open and close the discharge opening. A discharge valve that is in a position to close the discharge port when the discharge port is in a closed state and a position below the discharge port when the discharge port is in an open state, and the powdered solidified material is introduced into the cylinder An opening / closing opening provided on a side surface of the cylinder and an opening valve provided to be movable up and down relative to the cylinder in the cylinder so as to open / close the charging opening; When the inlet is in the open state, it is in a position above the inlet and A closing valve in a position to close the closing port when the closing port is closed, and a vertical direction to connect the discharging valve and the closing valve to interlock the vertical movement of the discharging valve and the closing valve. And a valve connecting rod extending.

(3) according solidifying material filling apparatus in claim 3, in claim 2, wherein the lower end shape of the discharge valve has a shape tapers downward.

( 4 ) The solidifying material filling apparatus according to claim 4 further includes a hydraulic cylinder for vertically moving the valve connecting rod relative to the cylindrical body according to claim 2 or 3 .

( 5 ) The solidifying material filling apparatus according to claim 5 is characterized in that in claim 2 or 3 , the solidifying material filling apparatus further includes a link cam for moving the valve connecting rod relatively up and down relative to the cylindrical body.

Since the present invention is configured as described above, the following effects can be expected.
The present invention is applied to the improvement of soft soil that is generated as a result of construction of various civil engineering and building structures. And the soil improved by this invention can be used effectively for construction of earth structures, such as the material of the embankment of a road, the bank of a river, etc., for example. Moreover, in order to enable construction of various civil engineering and building structures on soft ground, the present invention can also be applied to surface improvement of the soft ground. The method and apparatus of the present invention can be implemented inexpensively without using a large-scale apparatus or an apparatus having a complicated mechanism. Specifically, it is as follows.

(1) soft soil improvement method according to the present invention, since stirring is mixed with soft soil after filling the powdered solidifying material into a columnar hole provided in the deposited soft soil, spread on soft soil surface as in the prior art Compared with the case where it does, it can be filled in soft soil, without making a powdery solidification material touch air. Thereby, scattering of a solidification material can be prevented. In addition, since the solidified material filled in the soft soil absorbs moisture present in the soft soil at the same time as filling, the scattering of the solidified material is suppressed even when the soft soil and the solidified material are subsequently stirred. The As a result, it is possible to realize a construction that is favorable for the environment and health.

Further, in addition to the above-described effect of preventing the solidified material from being scattered, a wall of a columnar hole can be easily and quickly formed in the soft soil by press-fitting an appropriate cylinder into the soft soil. At the same time, at the time of press-fitting, the powdered solidified material has already been introduced into the cylindrical interior space. And when pulling up a cylinder, a powdery solidification material is discharge | released from the discharge port of a cylinder lower end part. Thereby, the filling of the powdered solidified material can be completed simultaneously with the completion of the cylinder lifting. In this preferred method, the formation of the columnar holes and the filling of the powdered solidified material can be performed at the same time, so that rapid construction is possible.

( 2 ) The solidifying material filling apparatus according to claim 2 is used for the soft soil improvement method according to claim 1 . This solidifying material filling device can be attached to a drive device for press-fitting and pulling up, and has a discharge valve provided so as to be relatively movable up and down at the bottom end of the cylinder for opening and closing the solid material discharge port, and a solidifying material A closing valve provided so as to be relatively movable up and down in the cylinder for opening and closing the charging opening is connected by a valve connecting rod extending in the vertical direction. Accordingly, the two valves are linked so that the closing valve is open when the discharge valve is closed, and conversely, when the discharge valve is open, the closing valve is closed. As a result, when the cylinder is press-fitted, the discharge valve is closed and the input valve is opened, and the powdered solidified material can be charged and stored in the cylinder from the input port. From this, the powdery solidified material can be discharged into the columnar hole.
The drive device for press-fitting and lifting is, for example, a drive device such as a general-purpose power shovel or a backhoe having a hydraulically driven arm capable of changing various attachments, and the solidified material of the present invention is attached to these arms as an attachment. By installing a filling device, low-cost construction is realized.

(3) solidifying material filling apparatus according to claim 3, since in addition to the effects described for the second aspect, the lower end shape of the discharge valve provided in the tubular body lower portion has a shape tapers downward, The resistance at the time of press-fitting the cylinder can be reduced, and the columnar holes can be formed quickly.

( 4 ) In addition to the effect described in claim 2 or 3 , the solidifying material filling device according to claim 4 or 5 moves the valve connecting rod up and down relatively with respect to the cylinder by the hydraulic device or the link device. As a result, the discharge valve and the closing valve can be opened and closed as needed, and can be quickly performed, so that the construction efficiency is improved.

Hereinafter, details of the embodiment will be described with reference to the drawings.
(1) Basic principle of soft soil improvement method (related to claim 1)
FIG. 1 is a diagram schematically showing the steps of the first embodiment of the soft soil improving method according to the present invention. This first form is the basic principle of the present invention.

  FIG. 1A schematically shows a state in which soft soil 1 to which the present invention is applied is deposited. Soft construction soils with high water content such as peat, highly hydrous clay, weathered volcanic ash, dredged soil, construction generated soil, etc. are secondaryly generated at construction sites related to construction and civil engineering. The generated soft soil is transported and accumulated in the site where the treatment according to the present invention is performed. In FIG. 1 (A), the deposited soft soil is schematically shown as a rectangular parallelepiped. For example, it is laid and deposited at a depth of about 50 to 100 cm on a site having an area of about several tens of meters in length and width. The target soft soil volume is arbitrary. As another example, when the present invention is applied to the surface layer of soft ground, FIG. 1 (A) corresponds to the surface layer of the target soft ground.

FIG. 1B shows a step of providing a columnar hole extending vertically downward from the surface with respect to the accumulated softness. The columnar hole 1a is a hole for filling a powdery solidified material (hereinafter, sometimes simply referred to as “solidified material”). The columnar hole 1a has a cylindrical shape in the illustrated example, but may have a polygonal columnar shape, and the cross-sectional shape may be arbitrary as long as it is a columnar hole having a depth almost reaching the deepest portion of the accumulated soft soil. The columnar hole 1a can be formed using a general civil engineering machine. As an example, the cross-sectional area of one columnar hole is about 100 cm ² and the depth is about 50 to 100 cm. A plurality of such columnar holes are formed in an appropriate arrangement. The volume of one columnar hole and the number of columnar holes to be formed can be set from the volume of the powdered solidified material to be mixed with the volume of the soft soil to be treated. The arrangement of the plurality of columnar holes is arranged without deviation with respect to the entire surface of the soft soil.

  FIG. 1 (C) shows a step of filling the formed columnar hole 1a with the powdered solidified material 2 and a step of stirring and mixing the soft soil 1 deposited together with the filled powdered solidified material 2. . The powdery solidifying material 2 is a cement-based solidifying material, cement-lime-based solidifying material, gypsum-based solidifying material or the like or a mixture thereof generally used in known ground improvement works. It is appropriately selected depending on the hardness of the improved soil. The powdery solidified material 2 filled in the columnar holes 1a absorbs moisture present in the surrounding soft soil 1 simultaneously with filling. Therefore, at this time, the powdered solidified material 2 is hardly scattered.

  In the columnar hole forming step and the solidifying material filling step shown in FIGS. 1B and 1C, a plurality of columnar holes 1a are first formed together, and then the solidifying material 2 is formed in the columnar holes 1a. However, it is of course possible to form a hole and fill the solidifying material 2 for each columnar hole 1a.

  When the solidified material 2 is filled in all the columnar holes 1a, the soft soil and the powdered solidified material are stirred and mixed using a general excavating machine such as a power shovel or a backhoe (see arrows). Since the powdery solidified material 2 has already absorbed a certain amount of water and is not easily scattered, the solidified material 2 is prevented from scattering even in this stirring and mixing step.

  FIG. 1 (D) shows the state of the improved soil 3 after completing the stirring and mixing. The solidified material 2 uniformly dispersed in the soft soil 1 is hardened by a hydration reaction with moisture in the soft soil 1, and the strength of the soft soil 1 is improved to become the improved soil 3.

(2) Suitable soft soil improvement method (related to claim 1 )
FIG. 2 is a diagram schematically showing the steps of the second mode of the soft soil improving method according to the present invention. This second form is a preferred form when implementing the basic principle of the first form described above.

  FIG. 2 (A) is a diagram schematically showing a solidifying material filling apparatus 10 used in a preferred soft soil improvement method. The solidifying material filling apparatus 10 has a cylindrical body 10a that can be press-fitted into accumulated soft soil. The cylinder 10a is provided with a discharge port 10b that can be opened and closed at the lower end thereof. The outer peripheral wall of the cylindrical body 10a corresponds to the hole wall shape of the columnar hole shown in the basic principle of FIG. Therefore, the cylinder 10a may be a cylinder or a square cylinder, but a cylindrical shape is preferable in consideration of ease of penetration into soft soil and ease of manufacture. The length of the cylindrical body 10a is set longer than the depth of the columnar hole to be formed, and the internal space has a volume capable of accommodating the amount of powdered solidified material filled in one columnar hole. The size of the discharge port 10b is appropriately set to such an extent that the powdered solidified material is quickly discharged downward from the inside of the cylinder 10a, and the opening / closing mechanism is arbitrary. For example, the suitable example of the solidification material filling apparatus by this invention shown in FIGS. 3-4 mentioned later is used. Cylindrical body 10a also includes an inlet 10c for feeding the powdered solidified material into the internal space. In the illustrated example, the upper end opening of the cylinder 10a is used as the insertion port 10c, but it may be provided on the side wall of the cylinder 10a.

  FIG. 2 (B) is a diagram showing a step of forming a columnar hole in soft soil. First, the discharge port 10b of the cylinder 10a prepared in FIG. 2 (A) is closed. Thereafter, the solidified solid material 2 in an amount to be filled in one columnar hole is put into the cylinder 10a, and the cylinder 10a is pressed into the accumulated soft earth 1 from the surface of the soft earth 1. A columnar hole extending vertically downward is formed. The cylinder 10a can be moved up and down by being attached to an arm of a drive machine including a hydraulic device used for a power shovel, a backhoe or the like. Thereby, the cylinder 10a is press-fitted and pulled up as will be described later. In addition, the powdery solidified material 2 should just be thrown in in the cylinder 10a by the time of the press injection of the cylinder 10a being completed. For example, it may be charged in advance before the start of press-fitting, or may be thrown in while press-fitting.

  FIG. 2C is a diagram illustrating a state where the press-fitting of the cylindrical body 10a is completed. The position of the lower end of the cylindrical body 10a at the time of completion of press-fitting is set to an extent that substantially corresponds to the deepest portion of the soft soil 1 as a target.

  FIG. 2 (D) is a diagram illustrating a process of pulling up the cylindrical body 10a and filling a powdery solidified material. In this process, first, after opening the discharge port 10b of the cylinder 10a, the cylinder 10a is started to be pulled up. Thus, the powder solidified material 2 is filled into the columnar hole 1a by pulling up the cylindrical body 10a while discharging the powdered solidified material 2 from the discharge port 10b into the columnar hole 1a.

  FIG. 2E is a diagram showing a state in which the pulling up of the cylindrical body 10a is completed. In this way, the formation of one columnar hole 1a and the filling of the powdered solidified material 2 into the columnar hole 1a are performed by one press-fitting and lifting operation of the cylindrical body 10a. Thereafter, the cylindrical body 10a is moved to form another columnar hole and to be filled with a powdered solidified material. By repeating this, a plurality of columnar holes filled with the powder solidifying material are formed on the entire surface of the soft soil without deviation.

  FIG. 2 (F) is a diagram showing a state after completion of the stirring and mixing step of the soft soil and the powdered solidified material. The stirring and mixing is performed using a power shovel, a backhoe, or the like as described with reference to FIG. In this way, the solidified material uniformly dispersed in the soft soil is hardened by the hydration reaction, and the strength of the soft soil is improved and the improved soil 3 is obtained.

(3) Solidifying material filling device used for soft soil improvement method (related to claims 2 to 5 )
FIG. 3 is a side sectional view schematically showing a preferred example of the solidifying material filling apparatus 10 used in the preferred soft soil improvement method shown in FIG. FIG. 3 shows a state where the solidifying material filling device 10 is attached to an arm 20 of a drive device such as a power shovel or a backhoe, which is a drive device for moving the entire solidifying material filling device 10 in the vertical direction.

  The solidifying material filling apparatus 10 has a cylindrical body 10a, and an attachment portion 18 for attachment to the arm 20 is provided at an upper end opening portion thereof. The cylindrical body 10a is preferably a cylindrical shape in order to reduce the resistance of soft soil during press-fitting, but may be a rectangular tube shape.

  A discharge port 10b is provided in the lower end opening of the cylindrical body 10a. A discharge valve 11 is provided at the lower end of the cylinder 10a so that the discharge port 10b can be opened and closed. The discharge valve 11 is movable up and down with respect to the discharge port 10b. That is, it can move up and down relatively with respect to the cylindrical body 10a. A tapered portion extending downward from the lower end opening of the cylindrical body 10a so as to approach the central axis serves as a valve seat 10d of the discharge valve 11. The shape of the lower half of the discharge valve 11 is a conical shape whose apex is directed downward. This is a shape for facilitating the advancement by reducing the resistance of soft soil when the solidifying material filling device 10 is press-fitted. The shape of the lower half of the discharge valve 11 is not limited to a conical shape as long as it tapers downward, and may be a pyramid shape.

  When the discharge port 10b is in the closed state, the discharge valve 11 is in a position to close the discharge port 10b. At this time, the discharge valve 11 and the discharge valve seat 10d are in close contact with each other. Thereby, the bottom part of the internal space 10e of the cylinder 10a is closed. On the other hand, when the discharge port 10b is in the open state, the discharge valve 11 is at a position below the discharge port 10b as shown. At this time, the discharge valve 11 and the valve seat 10d are separated and a gap is formed. This gap is set to such a size that the powdered solidified material accommodated in the internal space 10e of the cylindrical body 10a is quickly released.

  The vertical movement of the discharge valve 11 is performed by the vertical movement of the valve connecting rod 12 attached to the center of the upper end of the discharge valve 11 and extending upward in the vertical direction. Rod guides 15 and 16 for supporting the valve connecting rod 12 are provided in the internal space 10e. The rod guides 15 and 16 are, for example, a pair of support members that extend from a position opposed to the inner peripheral wall of the cylindrical body 10a toward the central axis, and support the valve connecting rod 12 from both sides. The valve connecting rod 12 is not fixed to the rod guides 15 and 16 and can slide along the rod guides 15 and 16. The rod guide 15 has a shape and a size that do not hinder the dropping operation of the solidified material when the powdered solidified material is discharged.

  Furthermore, the side surface of the cylindrical body 10a is provided with an inlet 10c for feeding the powdered solidified material into the internal space 10e. A solidified material delivery pipe 19 communicating with the outside is attached to the input port 10c. The powdery solidified material is transferred through the solidified material delivery pipe 19. The volume of the internal space 10e from the inlet 10c to the outlet 10b of the cylindrical body 10a is set so as to accommodate the amount of powdered solidified material that fills one columnar hole.

  A closing valve 13 is provided in the cylinder 10a to open and close the charging port 10c. In the illustrated example, the input valve 13 has a cylindrical shape that fits into the inner peripheral wall of the cylinder 10a, and can move up and down while sliding along the inner peripheral wall. That is, it can move up and down relatively with respect to the cylindrical body 10a. The outer peripheral edge of the lower surface of the input valve 13 is tapered, while an input valve seat 14 having a shape for receiving the tapered portion is provided in an annular shape along the inner peripheral wall of the cylindrical body 10a. The input valve seat 14 is positioned below the input port 10c.

  When the input port 10c is in the open state, the input valve 13 is in a position above the input port 10c and away from the input valve seat 14. At this time, the insertion port 10c communicates with the internal space 10e. On the other hand, when the input port 10c is in the closed state, as shown in the figure, the input valve 13 is in a position to close the input port 10c and is in close contact with the input valve seat 14.

  The input valve 13 is fixed to a valve connecting rod 12 that passes through the central axis thereof. Therefore, as the valve connecting rod 12 moves up and down, the closing valve 13 also moves up and down.

  Since both the discharge valve 11 and the closing valve 12 are fixed to the valve connecting rod 12 in this way, the vertical movement of both valves 11 and 13 can be linked by moving the valve connecting rod 12 up and down. Can do. Accordingly, the two valves 11 and 13 are interlocked so that the closing valve 13 is opened when the discharge valve 11 is closed, and conversely, when the discharge valve 11 is open, the closing valve 13 is closed. As a result, when the solidifying material filling device 10 is press-fitted, the discharge valve 11 is closed and the charging valve 13 is opened to allow the powdered solidifying material to be charged and stored in the internal space 10e from the charging port 10c. When pulling up, the discharge valve 11 can be opened to discharge the powdered solidified material from the discharge port 10b into the columnar hole.

  The lowest position of the valve connecting rod 12 is defined by the position where the closing valve 13 is in close contact with the closing valve seat 14 as shown in the figure. The uppermost position of the valve connecting rod 12 is defined by the position where the discharge valve 11 is in close contact with the discharge valve seat 10d.

  The valve connecting rod 12 of the solidifying material filling device 10 shown in FIG. 3 moves upward relative to the cylinder body due to the resistance of soft soil to the discharge valve 11 when the cylinder body is press-fitted. At this time, the discharge port 10b is closed and the input port 10c is opened. On the other hand, when the cylindrical body is pulled up, the valve connecting rod 12 moves downward relative to the cylindrical body by its own weight including the weights of the discharge valve 11 and the bar closing valve 13 connected. At this time, the discharge port 10b is opened and the input port 10c is closed. The method of the embodiment of FIG. 3 is referred to as a dead weight dropping method.

  In addition, it is preferable to provide the air bleeding and dust collecting device 17 at an appropriate position on the side surface of the cylindrical body 10a. The air bleeder / dust collector 17 sucks the air in the internal space 10e when the powdered solidified material is charged from the charging port 10c, thereby collecting the dust that rises at the same time as the solidified material is smoothly charged. So that

  Note that the “up and down movement” of the discharge valve 11, the valve connecting rod 12 and the closing valve 13 in the above description regarding the embodiment of FIG. To do.

  FIG. 4 is a side cross-sectional view schematically showing a process of a construction example in which the self-weight fall type solidifying material filling apparatus 10 of FIG. 3 is used in the soft soil improvement method of FIG.

  FIG. 4A is a diagram showing a state before the press-fitting start of the solidifying material filling device 10. The solidifying material filling device 10 is lifted by the arm 20 of the driving device. At this time, the discharge valve 11 is in the open state, the charging valve 13 is in the closed state, and the powdered solidifying material has not yet been charged.

  FIG. 4B is a diagram illustrating a state at the start of press-fitting of the solidifying material filling device 10. When the arm 20 is lowered, the tip of the discharge valve 13 comes into contact with the soft soil surface, and the discharge valve 13 is temporarily stopped due to the resistance. Subsequently, only the cylinder 10a moves downward (the valve connecting rod 12 moves relatively upward with respect to the cylinder 10a), the discharge valve seat 10d and the discharge valve 11 come into contact with each other, and the discharge port is closed. Thereafter, the entire solidifying material filling device 10 begins to be buried in soft soil. At this time, the closing valve 13 is opened at the same time. When the charging valve 13 is opened, the powdered solidified material 2 starts to be charged into the cylinder.

  FIG. 4C is a diagram showing a state during the press-fitting of the solidifying material filling device 10. The solidification material filling device 10 is pressed into soft soil by lowering the arm 20 while the powdered solidification material 2 is being introduced. The powder solidified material 2 is accumulated in the cylinder.

  FIG. 4D is a diagram showing a state when the press-fitting of the solidifying material filling device 10 is completed. The charging of the powder solidifying material 2 is also completed.

  FIG. 4E is a diagram showing a state when the solidifying material filling apparatus 10 starts to be pulled up. When the solidifying material filling device 10 starts to be pulled up by raising the arm 20, the cylindrical body 10a starts to rise. On the other hand, the valve connecting rod 12 that connects the discharge valve 11 and the closing valve 13 remains in its position due to its own weight.

  As a result, the discharge valve 11 moves away from the cylindrical body 10a and the discharge port starts to open, while the input valve 13 starts to close the input port. As a result, the powdery solidified material 2 starts to fall and be released from the opened discharge port into the columnar hole 1a. When the charging valve 13 hits the charging valve seat 14, thereafter, the entire solidifying material filling device 10 is pulled up with the discharge port open.

  FIG. 4F is a diagram showing a state in the middle of pulling up the solidifying material filling device 10. When the solidifying material filling apparatus 10 is further pulled up, the lower portion of the columnar hole 1a is in a vacuum state, and the powdered solidified material is sucked downward to be promoted to fall and accumulate in the columnar hole 1a. . In this way, in order to release the powdered solidified material while pulling up the solidified material filling device 10, the solidified material is adsorbed on the pore walls sufficiently containing water, so that the solidified material is sequentially deposited from below. Almost no diffusion or scattering.

  FIG. 4G is a diagram illustrating a state when the solidifying material filling device 10 is completely lifted. As shown in the figure, all of the powder solidified material falls into a columnar hole 1a formed in soft soil, and is not scattered or diffused at all in the air. Thereafter, as described with reference to FIGS. 1 and 2, the soft soil and the powdered solidified material are mixed with stirring.

  FIG. 5 is a view showing several embodiments of a valve opening / closing mechanism for moving the valve connecting rod 12 up and down. FIG. 5 (A) is the self-weight drop method shown in FIG. 3, in which the valve connecting rod 12 is in the uppermost position (at the time of press-fitting), the discharge valve 11 is closed, the input valve 13 is opened, and the powder solidified material 2 Shows a state in which is inserted into the cylinder 10a. When the valve connecting rod 12 is at the lowermost position (at the time of lifting), the discharge valve 11 is opened, the input valve 13 is closed, and the powdered solidified material 2 is discharged from the discharge port.

  FIG. 5B shows a hydraulic cylinder system. A hydraulic cylinder 19 is attached to the upper end of the valve connecting rod 12. By controlling the expansion / contraction operation of the hydraulic cylinder 19, the valve connecting rod 12 can be moved up and down relatively with respect to the cylindrical body 10a. The relationship between the opening and closing of the valve and the charging and discharging of the powdered solidified material is the same as in FIG. In this system, the valve can be opened and closed at any time. This mechanism is particularly effective in extremely soft ground.

  FIG. 5C shows a link cam mechanism system. A link cam is attached to the upper end of the valve connecting rod 12. The link cam is connected to the hydraulic cylinder of the drive unit. By rotating each link as shown by an arrow, the valve connecting rod 12 can be moved up and down relatively with respect to the cylindrical body 10a. The relationship between the opening and closing of the valve and the charging and discharging of the powdered solidified material is the same as in FIG. Even in this method, the valve can be opened and closed at any time.

  The various valve opening / closing mechanisms shown in FIG. 5 are selected according to the local land conditions, environment, driving device to be used, and the like.

It is a figure which shows typically the process of the 1st form of the soft soil improvement method by this invention. (A) schematically shows a state where soft soil 1 to which the present invention is applied is deposited. (B) shows a step of providing a columnar hole extending vertically downward from the surface with respect to the accumulated softness. (C) shows a step of filling the formed columnar hole 1a with the powdered solidifying material 2 and a step of stirring and mixing the soft soil 1 deposited together with the filled powdered solidifying material 2. (D) shows the state of the improved soil 3 after completing the stirring and mixing. It is a figure which shows typically the process of the 2nd form of the soft soil improvement method by this invention. The solidification material filling apparatus 10 used for the suitable soft soil improvement method is shown typically. (B) shows the process of forming columnar holes in soft soil. (C) shows a state where the press-fitting of the cylindrical body 10a is completed. (D) shows the process of pulling up the cylinder 10a and filling the powdered solidified material. (E) shows a state in which the pulling up of the cylindrical body 10a is completed. (F) shows the state after completion of the stirring and mixing step of the soft soil and the powdered solidified material. It is the sectional side view which showed schematically the suitable example of the solidification material filling apparatus 10 used for the suitable soft soil improvement method shown in FIG. It is a sectional side view which shows typically the process of the construction example which used the solidification material filling apparatus 10 of the self-weight fall system of FIG. 3 for the soft soil improvement method of FIG. (A) shows the state before the press-fitting start of the solidification material filling apparatus 10. (B) shows the state at the start of press-fitting of the solidifying material filling device 10. (C) shows a state during the press-fitting of the solidifying material filling device 10. (D) shows the state when the press-fitting of the solidifying material filling device 10 is completed. (E) shows the state when the solidifying material filling apparatus 10 starts to be pulled up. (F) shows a state in which the solidifying material filling device 10 is being pulled up. (G) shows the state when the solidifying material filling device 10 is completely lifted. It is the figure which showed some examples of the valve opening and closing mechanism which moves the valve connection rod 12 up and down. (A) is the dead weight dropping method shown in FIG. (B) is a hydraulic cylinder system. (C) is a link cam mechanism system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Soft soil 2 Solidified material 3 Improved soil 10 Solidified material filling apparatus 10a Tubular body 10b Release port 10c Input port 10d Release valve seat 10e Interior space 11 Release valve 12 Valve connection rod 13 Input valve 14 Input valve seat 15, 16 Rod guide 17 Air venting and dust collecting device 18 Mounting portion 19 Hydraulic cylinder 20 Backhoe tip arm 21 Link cam mechanism 25 Solidified material delivery pipe

Claims (5)

In a method for improving soft soil by mixing and solidifying a powdered solidified material,
The lower end of the tubular member to release the openable inlet open state Toshikatsu tubular body of powdered solidifying material for the deposited pressed capable cylindrical body in soft soil turning on the powdery solidification agent After the input port and the discharge port are interlocked so that the openable / closable discharge port provided in the section is closed, the powdered solidified material is charged into the cylindrical body from the charge port, and the Providing a columnar hole extending vertically downward from the surface of the soft soil by press-fitting the cylinder into the deposited soft soil;
After the charging port and the discharge port are interlocked so that the charging port of the cylindrical body is closed and the discharge port of the cylindrical body is opened , the powder solidifying material is released from the discharge port. Filling the powdery solidified material into the columnar holes by pulling up the cylindrical body while releasing
And a step of stirring and mixing the deposited soft soil together with the filled powdery solidified material. The solidifying material filling device used in the soft soil improvement method according to claim 1 , having the cylindrical body, and can be attached to a driving device for press-fitting and pulling up the accumulated soft soil,
A discharge valve provided at the lower end portion of the cylindrical body so as to be movable up and down relative to the cylindrical body so as to open and close the discharge port, the position closing the discharge port when the discharge port is closed A discharge valve at a position below the discharge port when the discharge port is open and
An openable / closable charging port provided on a side surface of the cylindrical body for charging the powdered solidified material into the cylindrical body;
A closing valve provided in the cylinder so as to be movable up and down relative to the cylinder so as to open and close the inlet, and is located above the inlet when the inlet is open. And an input valve in a position to close the input port when the input port is closed;
In order to link the discharge valve and the input valve vertically, the discharge valve and a valve connecting rod extending vertically to connect the input valve are used. Solidifying material filling device. The solidifying material filling apparatus according to claim 2 , wherein the lower end shape of the discharge valve is a shape that tapers downward. The solidifying material filling apparatus according to claim 2 , further comprising a hydraulic cylinder that moves the valve connecting rod up and down relatively with respect to the cylindrical body. The solidifying material filling device according to claim 2 , further comprising a link cam that moves the valve connecting rod up and down relatively with respect to the cylindrical body.

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