JP2006336256A - Jet mixing method and jet mixing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jet mixing method which is carried out by ejecting a reaction material and a soil improving medium in almost the same direction by first and second ejection sections arranged at a lower portion of a jet mixing apparatus, and ejecting a mixture of compressed air and water in a direction opposed to the direction in which the reaction material and the soil improving medium are ejected, by a third ejection section, and to provide the jet mixing apparatus for use in the method. <P>SOLUTION: According to the jet mixing method, as shown in Fig. 2, a rod of the jet mixing apparatus has the first and second ejection sections 42, 44 arranged at a lower end thereof, and the third ejection section 46 arranged at an upper portion than the first and second ejection sections 42, 44. The first ejection section 42 functions to eject the soil improving medium, the second ejection section 44 functions to eject the reaction material in almost the same direction as that of the first ejection section, and the third ejection section 46 functions to mix the compressed air and the water together and to eject the mixture in the direction opposed to the first and second ejection sections. The rod thus formed is pressed and squeezed or advanced into the ground, and while rotatively drawn from the ground, the rod ejects the compressed air and the water in a predetermined range to jet-cut a soil improvement range. Then cut sludge is discharged via an excavation hole onto the ground surface, and the reaction material is ejected from the second ejection section 44, followed by ejecting the soil improving medium from the first ejection section 42, to thereby construct a pile of a predetermined diameter. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a jet agitating method and a jet agitating apparatus for constructing a pile by impregnating a ground improvement medium into a soft ground, and in particular, a lower first injection part and a second injection part are a reaction material and a ground improvement. The present invention relates to a jet agitating method and a jet agitating apparatus for injecting compressed air and water mixed in a substantially same direction, and in which compressed air and water mixed in an upper third injecting direction are opposed to a reaction material and a ground improvement medium. .

2. Description of the Related Art Conventionally, in construction and civil engineering work, a method of hardening a ground by impregnating the ground with a ground hardener is used to harden the soft ground. Various methods have been proposed as a method for such ground improvement, and in particular, the jet agitation method is widely used from the viewpoint of workability and certainty.
For example, as disclosed in Japanese Patent Application No. 2003-379126, the conventional jet agitation method is a method in which compressed air and water are strongly jetted from the jet part provided on the rod to crush and cut the ground with water pressure. This is a construction method in which a ground improvement medium mainly composed of cement milk and a reaction material that accelerates hardening of the ground improvement medium are jetted and stirred to construct a pile having a predetermined diameter.

The conventional jet agitating device is provided so as to inject the injected material in a direction in which the first injection unit and the second injection unit are opposed to each other, and the third injection unit is in a direction in which the mixed compressed air and water face each other. It was the structure provided so that each might inject. By appropriately setting the construction conditions such as rotation speed and ascent speed, it is possible to quickly form a pile with sufficient strength by stirring the ground evenly within the required range and adding improvement materials and reaction materials. It is.
However, in the jet agitation method using the conventional jet agitation device, since the first injection part and the second injection part are provided in the opposing direction, the reaction material and the ground improvement medium are injected in the opposite direction. Depending on the condition of the ground and construction conditions, uneven stirring is likely to occur, and there were cases where the reaction material and the ground improvement medium were not properly mixed.
Development of a jet stirring method and a jet stirring device that can prevent the occurrence of uneven stirring and reliably mix the reaction material and the curing agent has been awaited.

Japanese Patent Application No. 2003-379126

  In order to solve the above problems, the jet stirring method and the jet stirring device of the present invention relate to the jet stirring method and the jet stirring device for constructing the pile by impregnating the ground improvement medium into the soft ground, The first injection unit and the second injection unit inject the reaction material and the ground improvement medium in substantially the same direction, and the upper third injection unit mixes the compressed air and water with the reaction material and the ground improvement. An object of the present invention is to provide a jet stirring method for jetting in a direction opposite to a medium for use and a jet stirring device used therefor.

  In order to achieve the above object, a jet agitating method and a jet agitating apparatus according to the present invention include a first jet part for jetting a ground improvement medium mainly composed of cement milk at a lower end, and the first jet part. A second injection unit for injecting the reaction material in substantially the same direction, and further mixing the compressed air and water at a higher level than the first and second injection units. A rod provided with a third injection portion that injects in a direction opposite to the ground is pressed into or advanced into the ground, and the rod is lifted while rotating the rod from the ground, while the third injection portion is within a predetermined range. Compressed air and water are jetted from the ground, and the ground improvement range is jetted and cut into a cylindrical shape, and the cut mud is discharged to the ground through a drilling hole, and the ground improvement medium is solidified from the nozzle of the second jet part Spray the material and then the nozzle of the first injection part Injecting medium for ground improvement, a method of constructing a pile of a given diameter.

  In the jet agitation method, the first injection unit and the second injection unit are arranged in parallel in the horizontal direction, and the injection ports are provided in substantially the same direction so that the injection directions are substantially parallel to each other. The reaction material and the ground improvement medium are also sprayed horizontally and in parallel in the same direction. Further, in the jet stirring method according to claim 2, the second injection portion for injecting the reaction material is provided on a predetermined dimension from the first injection portion for injecting the ground improvement medium, and the rod rotates and rises. By this, it is also a construction method in which the reaction material is first mixed with the ground and the ground improvement medium is mixed later. Further, in the jet agitation method, a second injection unit for injecting the reaction material to the front side with respect to the rotation direction of the rod is provided, and a ground improvement medium mainly composed of cement milk is injected to the lower end on the rear side. The first injection part is provided, and the reaction material is first mixed with the ground by rotating the rod, and the ground improvement medium is mixed later.

  In the jet agitation method, a solid medium having a certain particle size or more is separated and removed from the mud containing the mud containing water discharged to the surface and mixed with the ground improvement medium to form a mixed medium. It is also a method of injecting a mixed medium as a ground improvement medium from an injection part. In the jet agitation method, solid matter having a certain particle size or more is separated and removed from the mud containing the mud containing water discharged to the surface, and mixed with the ground improvement medium to form a mixed medium. It is also a method of injecting the mixed medium as a ground improvement medium from the first injection unit by pumping.

  Provided at the lower end is a first injection part for injecting a ground improvement medium mainly composed of cement milk, and a second injection part for injecting a reaction material in substantially the same direction as the first injection part, A rod provided with a third injection part that mixes compressed air and water in an upper stage than the first and second injection parts and injects the air in a direction opposite to the first and second injection parts. While pushing and entering or feeding, pulling up while rotating the rod from the ground, injecting compressed air and water from the third injection unit within a predetermined range to inject and cut the ground improvement range into a cylindrical shape, The cut mud is discharged to the ground through the drilling hole, the reaction material that solidifies the ground improvement medium is injected from the nozzle of the second injection part, and the ground improvement medium is injected from the nozzle of the first injection part. And it is the structure which builds the pile of a predetermined diameter.

  In the jet agitating device, the first jet part and the second jet part are arranged in parallel in the horizontal direction, and the jet ports are provided in substantially the same direction so that the jet directions are substantially parallel to each other. The reaction material and the ground improvement medium are also jetted horizontally and in parallel in the same direction. 8. The jet agitating apparatus according to claim 7, wherein the second jetting unit for jetting the reaction material is provided on a predetermined dimension from the first jetting unit for jetting the ground improvement medium, and the rod rotates and rises. The reaction material is mixed with the ground first, and the ground improvement medium is mixed later. In the jet stirring device, a second jetting unit for jetting the reaction material to the front side with respect to the rotation direction of the rod is provided, and a ground improving medium mainly containing cement milk is jetted to the lower end on the rear side. One injection unit is provided, and the reaction material is mixed with the ground first by rotating the rod, and the ground improvement medium is mixed later.

As described above in detail, the jet stirring method and the jet stirring apparatus according to the present invention are configured as described above, and thus have the following effects.
1. The force generated by the injection of the reaction material and the ground improvement medium in the lower stage of the rod is generated in the opposite direction to the force generated by the jet of compressed air and water mixed in the upper stage, so a large load in a specific direction during construction It is possible to prevent the rod from being bent and the rotation axis of the rod from shifting.
2. Since the injection direction of the reaction material and the ground improvement medium is substantially parallel to the horizontal direction, it is possible to reliably impregnate the ground with the reaction material and the ground effect medium and to prevent uneven stirring. .

3. Since the reaction material is first mixed with the ground, the reaction material is uniformly mixed with the ground first, and a jet stirring method that can prevent stirring unevenness can be provided.
4). Since the injection part of the reaction material is provided at a predetermined distance from the injection part of the ground improvement medium, the reaction material is uniformly mixed first with respect to the ground, and uneven stirring can be prevented. A jet stirring method can be provided.
5. Originally, solid matter having a certain particle size or less is removed from waste mud that is treated as industrial waste, and the waste mud is reused. Therefore, it is possible to provide an economical and environmentally friendly jet stirring method.
6). By using a pressure pump, even if mud soil having a relatively large particle size is mixed with the ground improvement medium, injection can be easily performed.

7). Since the force generated by the injection from the first and second injection parts at the lower stage of the rod and the force generated by the injection from the third injection part at the upper stage are generated in the opposite direction, This is a jet agitating device that can prevent the rod from being bent due to a large load and the rotation axis of the rod from shifting.
8). Since the injection directions from the first and second injection sections are substantially parallel to the horizontal direction, it is possible to reliably impregnate the ground with the reaction material and the ground effect medium and to prevent stirring unevenness. I can do it.
9. Since the reaction material is mixed first with respect to the ground, the reaction material is uniformly mixed with the ground first, and stirring unevenness can be prevented.
10. Since the injection part of the reaction material is provided at a predetermined distance from the injection part of the ground improvement medium, the reaction material is uniformly mixed first with respect to the ground, and uneven stirring can be prevented. .

The jet stirring method and the jet stirring apparatus according to the present invention will be described below in detail according to embodiments shown in the drawings. FIG. 1 is a schematic view of a jet stirring apparatus of the present invention, and FIG. 2 is a cross-sectional view of a rod of the jet stirring apparatus of the present invention. FIG. 3 is an enlarged view of the vicinity of the first injection unit and the second injection unit of the jet agitating apparatus according to the first embodiment of the present invention, and FIG. 4 shows the first of the jet agitating apparatus according to the second embodiment of the present invention. It is an enlarged view of the vicinity of the injection unit and the second injection unit.
As shown in FIG. 1, the jet agitating device 10 of the present invention includes a drive device 20, a press approach device 30 (a feeding device), and a rod 40. Moreover, although not shown in figure, each pump for separately pumping water, compressed air, a ground improvement medium, and a reaction material is provided in the rod 40 as an essential component. About the drive device 20 and the press approach apparatus 30, if it is sufficient to use the thing similar to a prior art, the detail is explained in full detail as needed.

The rod 40 shown in the drawing is a multi-circular tube, and is provided with a first injection part and a second injection part with the injection ports directed in substantially the same direction, than the first and second injection parts. In the upper stage, a third injection unit is provided in which the injection port is directed in a direction almost opposite to that of the first and second injection units. Moreover, the flow path which supplies water, compressed air, the ground improvement medium, and the reaction material to each injection part to each injection part is provided in the inside of a rod, and an injection material is supplied to each injection part.
The internal configuration of the rod is not limited to the configuration shown in the figure. For example, four pipes with different diameters are arranged in multiple layers, and water, compressed air, ground improvement medium, and reactants are mixed and pressurized separately through the gaps between the pipes. It is good also as a structure which injects. Moreover, although the mixing part which mixes compressed air and water is provided in the 3rd injection part vicinity mentioned later, the method of mixing and the structure of a mixing part are not specifically limited.

The first injection unit 42 is an injection port that injects a ground improvement medium mainly composed of a hardener such as cement milk, and the second injection unit 44 reacts in substantially the same direction as the first injection unit. It is an injection port which injects material. The nozzle shape and the like of the injection unit may be appropriately determined in consideration of the properties of the ground improvement medium and the reaction material to be used, and are not particularly limited.
As the ground improvement medium and the reaction material, those used in the conventional jet stirring method can be used as they are. The main component of the ground improvement medium used in the conventional ground stirring method is a hardener such as cement milk. Moreover, it is also possible to mix the residual soil obtained by separating and removing solids having a specific particle size or more from the mud discharged during the construction of the jet stirring method with a curing agent and use it as a medium for ground improvement. As a method for separating and removing the solid matter, a method using a sieve or the like can be considered, but the method is not limited to a specific method. As the reaction material, water glass, sodium silicate, or the like that reacts with cement milk or the like to accelerate hardening is used. The ground improvement medium and the reaction material need only be able to cure or modify the ground by reacting by mixing, and the material chemical composition is not particularly limited.

  The arrangement relationship between the first injection unit 42 and the second injection unit 44 is not limited to a particularly fine position, as long as each can inject the injection in substantially the same direction. As the simplest arrangement, a configuration in which the first and second injection units are arranged in parallel vertically is conceivable. However, in the present invention, in order to reduce the unevenness of stirring between the reaction material and the ground improvement medium, the first and second injection portions are arranged in parallel or with a small step as shown in FIGS. The arranged configuration is adopted. The configuration in which the first injection unit 42 and the second injection unit 44 are provided as shown in FIG. 3 or FIG. 4 will be described in detail in each embodiment described later.

  The injection directions of the first injection unit 42 and the second injection unit 44 are preferably parallel to each other, but may not be injected in a completely parallel state. Even if each injection unit is arranged in parallel in the horizontal direction and the injection direction is injected perpendicular to the rod, the direction of the force applied to the rod is the direction of the resultant force of both injections. The direction of the first injection unit 42 and the second injection unit 44 can be arbitrarily set by appropriately determining the installation position, injection direction, and height of a third injection unit 46 to be described later. However, if the injection direction in which the reaction material and the ground improvement medium are injected in parallel is unified, it is considered that the arrangement of the third injection unit 46 can be easily determined.

The third injection unit 46 is substantially the same as the force generated by the reaction when the injection is injected from the first and second injection units above the first injection unit 42 and the second injection unit 44. It is an injection port that mixes and injects compressed air and water in the same direction. Similarly to the first and second injection units, the nozzle shape of the injection unit is not particularly limited as long as it is a shape capable of injecting compressed air and water at a predetermined pressure.
The position of the third injection unit 46 needs to be determined in consideration of the installation positions of the first and second injection units, the injection direction of the injection, and the force generated on the rod during injection. For example, when the first and second injection units are injected in a specific direction in parallel, the third injection unit is provided so as to inject in a direction opposite to the first and second injection units. That's fine. Moreover, when the injection directions of the first and second injection units are slightly different, it can be determined based on the resultant force generated by each injection unit.

Based on FIG. 1, the difference between the jet stirring method of the present invention and the conventional jet stirring method will be described in detail. First, the rod 40 is pressed and entered to an arbitrary depth in the ground. Next, while pulling up while rotating the rod, compressed air and water reaching a predetermined range are injected from the third injection portion 46 to form a cylindrical cutting portion (ground improvement region) centering on the rod. To do. The jet agitating apparatus 10 of the present invention is configured to inject compressed air and water in only one direction, but by setting the rotation speed or the like as appropriate, the same function and effect as a conventional apparatus for injecting in both directions can be obtained. . At the same time as the third injection unit 46 starts injection, the rod is affected by the force generated by the reaction of the injection.
Waste mud consisting of pebbles, soil and water generated by cutting and crushing is sucked and discharged to the ground surface through a borehole. Waste mud generally needs to be treated as industrial waste, but after removing moisture from the mud, take out solids of a certain particle size and mix the remaining waste mud with ground improvement media for reuse. Is possible. This point is considered to be greatly different from the conventional technology.

  Next, the rod 40 is gradually raised, and when the lower first injection unit 42 and the second injection unit 44 reach the ground improvement region, the reaction material is injected from the second injection unit 44, The ground improvement medium is ejected from the ejection unit 42. Each projectile is mixed and stirred in the ground improvement zone. Further, the rod 40 is affected by the force generated by the injection in the opposite direction to the third injection unit 46 at the same time when the first and second injection units start the injection. Since the force in the opposite direction is applied, the deflection of the rod is minimized, so that the rotation shaft of the rod is prevented from shaking. In addition, after mixing, the reaction material and the ground improvement medium react to solidify, and a pile is formed.

  Hereinafter, embodiments of the jet stirring method and the jet stirring device that are characteristic in the positions where the first jet portion 42 and the second jet portion 44 are disposed will be described in detail with reference to the drawings.

With reference to FIG. 3, the jet stirring method and the jet stirring apparatus of Example 1 will be described in detail. In the jet stirring device 10 used in the jet stirring method of this embodiment, the first jet portion 42 and the second jet portion 44 are arranged in parallel in the horizontal direction so that the jet directions are substantially parallel to each other. Is characterized in that the injection ports are provided in substantially the same direction. Moreover, it is the structure which has arrange | positioned the 2nd injection part 44 in the front side with respect to the rotation direction of a rod, and has arrange | positioned the 1st injection part 42 in the rear side.
In the present invention, the second agitation unit 44 that injects the reaction material on the front side in the rotation direction of the rod is provided, and the reaction material is mixed with the ground first, and then the ground improvement medium is mixed later. The construction method is disclosed. The rotation direction of the rod of this embodiment is the direction of the arrow shown in the figure. In addition, depending on the properties of the ground improvement medium and the reaction material to be used, it may be possible to obtain a better effect by mixing the ground improvement medium first. In that case, what is necessary is just to set it as the structure which replaced the position of the 1st and 2nd injection part.

  In the jet stirring method and the jet stirring device of this embodiment, the first jet portion 42 and the second jet portion 44 are positioned at the same height. Therefore, according to the rotation of the rod, the reaction material is first mixed with the ground, and immediately after that, the ground improvement medium is jetted and mixed. This is particularly effective when the reaction material and the ground improvement medium are to be mixed quickly. As for the position of the structure 1st injection part 42 and the 2nd injection part 44, both should just be arrange | positioned at the same height. Further, the angle of the injection port is not particularly limited, but it is desirable that the injection directions from the injection units be as parallel as possible.

With reference to FIG. 4, the jet stirring method and the jet stirring apparatus of Example 2 will be described in detail. In the jet agitating apparatus 10 used in the jet agitating method of this embodiment, the second injection unit 44 is arranged on a predetermined dimension with respect to the first injection unit 42, and the injection is performed so that the injection directions are substantially parallel to each other. It is characterized in that the mouth is provided in substantially the same direction. Moreover, it is the structure which has arrange | positioned the 2nd injection part 44 in the front side with respect to the rotation direction of a rod, and has arrange | positioned the 1st injection part 42 in the rear side.
In the jet agitation method of this embodiment, the second injection part 44 for injecting the reaction material is positioned above the first injection part 42 so that the reaction material is grounded before the ground improvement medium. To be mixed. The upper position of the second injection unit 44 relative to the first injection unit 42 is not particularly limited, but an appropriate position close so that the reaction material and the ground improvement medium can be mixed without uneven mixing. Should be selected.

Schematic of the jet stirring device of the present invention Sectional drawing of the rod of the jet stirring apparatus of the present invention The enlarged view of the 1st injection part of the injection stirring apparatus of Example 1 of this invention, and the 2nd injection part vicinity The enlarged view of the vicinity of the 1st injection part of the injection stirring apparatus of Example 2 of this invention, and the 2nd injection part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Injection stirring apparatus 20 Drive apparatus 30 Press approach apparatus 40 Rod 42 1st injection part 44 2nd injection part 46 3rd injection part

Claims (10)

Provided at the lower end is a first injection part for injecting a ground improvement medium mainly composed of cement milk, and a second injection part for injecting a reaction material in substantially the same direction as the first injection part, A rod provided with a third injection part that mixes compressed air and water in an upper stage than the first and second injection parts and injects the air in a direction opposite to the first and second injection parts. While pushing and entering or feeding, pulling up while rotating the rod from the ground, injecting compressed air and water from the third injection unit within a predetermined range to inject and cut the ground improvement range into a cylindrical shape, In addition to discharging the cut mud to the surface through the drilling hole,
A jet agitation method for injecting a reaction material for solidifying a ground improvement medium from the nozzle of the second injection unit, and further injecting a ground improvement medium from the nozzle of the first injection unit to construct a pile having a predetermined diameter In the jet stirring method,
The first injection unit and the second injection unit are arranged in parallel in the horizontal direction, and the injection ports are provided in substantially the same direction so that the injection directions are substantially parallel to each other, and the reaction material and the ground improvement The jet stirring method according to claim 1, wherein the working medium is jetted horizontally and parallel to the same direction. In the jet stirring method according to claim 2,
The second injection part for injecting the reaction material is provided on a predetermined dimension than the first injection part for injecting the ground improvement medium, and the reaction material is mixed with the ground first by rotating and raising the rod. 3. The jet stirring method according to claim 2, wherein the ground improvement medium is mixed later. In the jet stirring method,
A second injection unit for injecting the reaction material to the front side with respect to the rotation direction of the rod is provided, and a first injection unit for injecting a ground improvement medium mainly composed of cement milk to the lower end is provided on the rear side. The jet stirring method according to any one of claims 1 to 3, wherein the reaction material is mixed with the ground first by rotating the rod, and the ground improvement medium is mixed later. In the jet stirring method,
Solid matter of a certain particle size or more is separated and removed from the waste mud composed of mud containing water discharged to the ground surface and mixed with the ground improvement medium to form a mixed medium, and the ground is improved from the first injection section. 5. The jet stirring method according to claim 1, wherein a mixed medium is jetted as the medium. In the jet stirring method,
A solid medium having a predetermined particle size or larger is separated and removed from the mud containing the mud containing water discharged to the ground surface, mixed with the ground improvement medium to form a mixed medium, and pumped with a pressure pump. 6. The jet stirring method according to claim 5, wherein the mixed medium is jetted from the jet section as a ground improvement medium. Provided at the lower end is a first injection part for injecting a ground improvement medium mainly composed of cement milk, and a second injection part for injecting a reaction material in substantially the same direction as the first injection part, A rod provided with a third injection part that mixes compressed air and water in an upper stage than the first and second injection parts and injects the air in a direction opposite to the first and second injection parts. While pushing and entering or feeding, pulling up while rotating the rod from the ground, injecting compressed air and water from the third injection unit within a predetermined range to inject and cut the ground improvement range into a cylindrical shape, In addition to discharging the cut mud to the surface through the drilling hole,
A jet agitating device for injecting a reaction material for solidifying a ground improvement medium from the nozzle of the second injection unit, and further injecting a ground improvement medium from the nozzle of the first injection unit to construct a pile having a predetermined diameter In the jet stirring device,
The first injection unit and the second injection unit are arranged in parallel in the horizontal direction, and the injection ports are provided in substantially the same direction so that the injection directions are substantially parallel to each other. The jet stirring device according to claim 7, wherein the working medium is jetted horizontally and in parallel in the same direction. In the jet stirring device according to claim 7,
The second injection part for injecting the reaction material is provided on a predetermined dimension than the first injection part for injecting the ground improvement medium, and the reaction material is mixed with the ground first by rotating and raising the rod. The jet agitating device according to claim 7, wherein the ground improvement medium is mixed later. In the jet stirring device,
A second injection unit for injecting the reaction material to the front side with respect to the rotation direction of the rod is provided, and a first injection unit for injecting a ground improvement medium mainly composed of cement milk to the lower end is provided on the rear side. 10. The jet agitating device according to claim 7, wherein the reaction material is mixed with the ground first by rotating the rod, and the ground improvement medium is mixed later.

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