JP2004019221A - Jet agitating device using cross jet stream - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a jet agitating device using cross jet streams capable of preventing direct application of resistance of ground soil to a jet stream discharge part to simplify the device structure, efficiently injecting high pressure jet, and dispensing with preceding excavation to smoothly perform soil improving work. <P>SOLUTION: A monitor part 10A is constituted by being provided with an excavating blade 12 provided at the lowest end part of an insert pipe 11, an agitating blade 13 provided above the excavation blade 12 on the inert pipe 11, and an upper and a lower jet stream discharge parts 14 and 15 provided at a prescribed interval in a vertical direction of the insert pipe 11. The agitating blade 13 is composed of an upper and a lower agitating blades 13A and 13B vertically forming a pair to respectively correspond to the upper and lower jet stream discharge parts 14 and 15. The upper and the lower jet stream discharge parts 14 and 15 can thus be respectively covered with the upper and the lower agitating blades 13A and 13B ahead of them in their moving direction, thereby direct application of ground soil resistance is prevented from acting to the upper and the lower jet stream discharge parts 14 and 15 when the insert pipe 11 is rotated. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an injection stirrer in which a hardened material is injected and agitated into the ground at a high pressure to form a consolidated pile, and in particular, an injection using a cross jet which injects a hardened material so as to cross each other from above and below. It relates to a stirring device.
[0002]
[Prior art]
As a method of ground improvement, for example, as disclosed in Japanese Patent Publication No. Hei 7-30552, a consolidated pile is formed in the ground using a jet stirring device provided with at least two jet discharge sections in an insertion pipe. There is a method.
[0003]
That is, in this jet stirring device, a high-pressure jet of a hardening material is jetted at a predetermined radius from nozzles as at least two jet discharge units provided at appropriate intervals in the longitudinal direction of an insertion pipe inserted into the ground. By making them intersect, a solidified pile having a predetermined diameter and a columnar shape is formed in the ground.
[0004]
[Problems to be solved by the invention]
However, in such a conventional jet stirrer, the jet discharge section for jetting a high-pressure jet is provided directly on the insertion pipe, so that when the insertion pipe is inserted into the ground, the resistance of the ground soil is reduced by the jet discharge section. Therefore, it is necessary to increase the strength of the jet discharge portion itself and its mounting strength, which increases the cost and size of the device.
[0005]
In addition, since the jet discharge section provided in the insertion pipe is directly buried in the ground soil, the high-pressure jet immediately after the injection, the ground soil becomes an obstacle, and the injection distance decreases.
[0006]
Further, since the stirring pipe is not provided in the insertion pipe of the jet stirring apparatus and the excavating wing is not provided at the lower end thereof, a pre-drilling is required in the previous process, and the work process of ground improvement is required. Will increase.
[0007]
Therefore, the present invention has been made in view of such a conventional problem, and aims at simplifying the structure of the device by preventing the resistance of the ground soil from directly acting on the jet discharge portion, and efficiently using the high-pressure jet. It is an object of the present invention to provide an injection stirrer using a cross jet, which injects and can perform a ground improvement operation smoothly without the need for preceding excavation.
[0008]
[Means for Solving the Problems]
In order to achieve this object, in the invention of claim 1, a drilling wing provided at the lowermost end of an insertion pipe that can rotate and ascend and descend, and a stirring blade provided above the drilling wing of the insertion pipe are provided. An upper and lower jet discharge unit for jetting water or hardening material so that the jet directions intersect with each other, provided at predetermined intervals in the vertical direction of the insertion tube, and constitute a monitor part, Upper and lower agitating blades are paired up and down corresponding to the upper and lower jet discharge portions, respectively. These upper and lower stirring blades cover at least the front side of the corresponding upper and lower jet discharge portions in the moving direction. It is characterized by having.
[0009]
In this case, since the upper and lower jet discharge sections are covered at least on the front side in the moving direction by the upper stirring blade and the lower stirring blade, the resistance of the soil when rotating the insertion pipe is increased by the upper and lower jet discharge sections. Direct action can be prevented.
[0010]
Moreover, the ground can be excavated with the rotation of the insertion pipe by the excavation wing provided at the lowermost end of the insertion pipe, and the insertion pipe can be inserted into the ground.
[0011]
According to a second aspect of the present invention, in the injection and agitation device using the cross jet according to the first aspect, the upper and lower agitating blades are formed in a hollow shape in which a hollow portion is formed in an axial direction perpendicular to the insertion pipe. , And the corresponding upper and lower jet discharge sections are disposed in the hollow portions of the lower stirring blades.
[0012]
In this case, since the upper and lower jet discharge sections are covered by the hollow upper and lower stirring blades, it is possible to prevent the resistance of the ground soil from acting on the jet discharge section, and, of course, from the jet discharge section. The jet immediately after injection can be protected from the ground soil.
[0013]
According to a third aspect of the present invention, in the injection stirrer using the cross jets according to the first or second aspect, the turning radius of each of the upper and lower stirring blades is set to be substantially the same as the turning radius of the excavating blade. It is characterized by being formed.
[0014]
In this case, since the upper and lower stirring blades have the same radius of gyration as the excavating wings, when penetrating into the ground, the original ground corresponding to the radius of gyration of the excavating wings is disturbed by the stirring wings, and the slurry is discharged at the time of withdrawal. The slime can be secured with the slime.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0016]
1 to 5 show an embodiment of a jet stirring device using a cross jet according to the present invention. FIG. 1 is a sectional front view showing a monitor portion of the jet stirring device, and FIG. 2 shows a monitor portion of the jet stirring device. FIG. 3 is an enlarged sectional view of a portion A in FIG. 1, FIG. 4 is an enlarged sectional view taken along line BB in FIG. 1, and FIG. 5 is a side view of a crane to which a jet stirring device is attached.
[0017]
As shown in FIG. 1, the jet stirrer 10 of the present embodiment is provided with a digging blade 12 provided at the lowermost end of an insertion tube 11 that can rotate and move up and down, and provided above the digging blade 12 of the insertion tube 11. The monitor portion 10A includes the stirring blade 13 and upper and lower jet discharge sections 14 and 15 provided at predetermined intervals in the vertical direction of the insertion tube 13.
[0018]
In addition, another insertion tube is connected to the upper end of the insertion tube 11 shown in FIG. 1 so as to have a required length.
[0019]
Then, as shown in FIG. 5, the jet stirring device 10 is set on a swivel 21 of a crane 20, supplies water or a hardening material from a compressor (not shown) to the insertion tube 11, and rotates the insertion tube 11. It descends and rises.
[0020]
The insertion tube 11 is formed in a thick-walled tube having a central passage 11a for supplying water or a hardening material at a central portion thereof. Water or a hardening material is injected into the center passage 11a from the swivel 21 at a high pressure. As the hardening material, cement milk, mortar, chemicals and the like are used.
[0021]
As shown in FIGS. 1 and 2, the excavating wing 12 has a plurality of excavating blades 12 b projecting downward from a main body portion 12 a connected to a lower end portion of the inserting tube 11 via bolts B, and The excavating blade 12b excavates the ground with the rotation and lowering of the eleventh.
[0022]
The stirring blade 13 is composed of an upper stirring blade 13A and a lower stirring blade 13B which are provided as a pair in the upper and lower directions corresponding to the upper and lower jet discharge units 14 and 15, respectively. The upper, lower stirring blade 13A, 13B is to pair projecting symmetrically from both sides of each insertion tube 11, each of the protrusion amount is as substantially the same diameter rotating radius R ₁ is the rotation radius R ₂ of the drilling blades 12.
[0023]
The upper stirring blade 13A covers at least the front side of the upper jet discharge section 14 in the moving direction, and the lower stirring blade 13B covers at least the front side of the lower jet discharge section 15 in the moving direction. The moving directions of the upper and lower jet discharge sections 14 and 15 are directions in which the insertion pipe 11 moves as it rotates and moves up and down.
[0024]
As a specific structure for covering the front side in the moving direction of the upper and lower jet discharge sections 14 and 15, the upper and lower stirring blades 13A and 13B are arranged in the directions of axes C ₁ and C ₂ perpendicular to the insertion pipe 11 as shown in FIG. The hollow portions 13Aa and 13Ba having a rectangular cross section are formed in the hollow portions 13Aa and 13Ba, and the upper and lower jet discharge portions 14 and 15 corresponding to the hollow portions 13Aa and 13Ba respectively are arranged in these hollow portions 13Aa and 13Ba.
[0025]
The upper and lower jet discharge sections 14 and 15 are connected to the center passage 11a by screwing nozzles 14a and 15a to the side wall of the insertion pipe 11 as shown in detail in FIG. The water or the hardening material fed to the central passage 11a is ejected from the nozzles 14a and 15a.
[0026]
Further, the nozzle 14a of the upper jet discharge unit 14 is inclined downward with respect to the center axis of the insertion tube 11, and the nozzle 15a of the lower jet discharge unit 15 is inclined upward with respect to the center axis of the insertion tube 11. The injection directions of the nozzles 14a and 15a intersect at a point P at a predetermined distance (radius) L from the center axis of the insertion tube 11.
[0027]
In this case, the downward and upward inclination directions of both nozzles 14a and 15a are equiangular, and are set at an angle of 25 ° with respect to the horizontal line as shown in FIG.
[0028]
As shown in FIG. 4, the upper and lower jet discharge portions 14 and 15 are configured such that the injection ports of the nozzles 14 a and 15 a communicate with a pair of air passages 11 b formed on the side of the center passage 11 a of the insertion pipe 11. The air in the air passage 11b mixes with the water or the hardening material injected from the nozzles 14a and 15a to form an ejector.
[0029]
The lower wall portion 13Ab of the hollow upper stirring blade 13A is inclined downward so as not to obstruct the injection direction of the nozzle 14a, and the upper wall portion 13Bb of the lower stirring blade 13B is similarly connected to the nozzle 15a. Is inclined upward so as not to hinder the injection direction of the nozzle.
[0030]
When performing construction using the jet stirring device 10 of the present embodiment with the above configuration, first, as shown in FIG. 5, the crane 20 is set at a predetermined position, and the insertion pipe 11 rotates and penetrates the ground. In this case, water is injected from the nozzles 14a and 15a of the upper and lower jet discharge sections 14 and 15 depending on the soil properties of the ground, and the excavating blade 12 and the upper and lower stirring blades 13A and 13B are intruded while the jet stirring device 10 is penetrating. by the rotation, it disrupts original ground in turning radius R ₂ of the drilling blades 12.
[0031]
After the penetration into the predetermined depth is completed, the insertion pipe 11 is moved upward while injecting the hardening material from the nozzles 14a and 15a of the upper and lower jet discharge sections 14 and 15. At this time, the cross jets jetted from the nozzles 14a and 15a intersect at a point P, and the point P rises while drawing a spiral trajectory as the insertion tube 11 rotates and rises.
[0032]
When the insertion pipe 11 rises in this way, the upper and lower stirring blades 13A and 13B and the excavation blade 12 rise while rotating in the stirred ground soil. However, the hollow portions 13Aa and 13Aa of the upper and lower stirring blades 13A and 13B rise. Since the upper and lower jet discharge sections 14 and 15 arranged in the 13Bb are covered by the upper and lower stirring blades 13A and 13B, it is possible to prevent the resistance of the ground soil from directly acting on these jet discharge sections 14 and 15. Can be.
[0033]
Accordingly, it is not necessary to excessively increase the strengths of the upper and lower jet discharge sections 14 and 15 and the mounting strength thereof, so that the structure of the jet stirring device 10 can be simplified, and the cost can be reduced accordingly. Can be.
[0034]
Further, since the upper and lower jet discharge sections 14 and 15 are covered with the upper and lower stirring blades 13A and 13B, the stirring blades 13A and 13B rotate toward the momentary gap formed by separating the ground soil by rotation. A jet can be injected from 14a and 15a.
[0035]
Therefore, since the jet can be prevented from being disturbed by the ground soil immediately after the injection, the cutting distance by the jet can be increased to increase the formed diameter, and the cutting length can be stabilized, and thus water or hardened material can be removed. The pump to be pumped can be downsized.
[0036]
In addition, since the jet stirring device 10 of the present embodiment is provided with the excavation wings 12 at the lowermost end of the insertion pipe 11, the ground is excavated with the excavation wings 12 with the rotation of the insertion pipe 11, and the insertion pipe 11 is removed. Since it can be inserted into the ground, it is not necessary to perform a pre-drilling in the previous process, and the work process for ground improvement can be simplified.
[0037]
At this time, when the insertion pipe 11 is inserted into the ground, since the upper and lower stirring blades 13A and 13B have the same radius of gyration as the excavating blade 12, the excavating blade 12 and the upper and lower stirring blades 13A and 13B are used. Then, the ground is disturbed, and the disturbed portion can be sufficiently softened.
[0038]
Therefore, the slime generated when the hardening material is injected from the nozzles 14a and 15a can be smoothly lifted and discharged from the soft ground.
[0039]
Furthermore, when the insertion pipe 11 is raised, the excavating wing 12 and the stirring blades 13A and 13B rotate to stir and mix the discharged hardened material and the ground soil to increase the stirring efficiency, thereby improving the quality of the consolidated pile. Can be.
[0040]
By the way, when pulling out the monitor part by raising the insertion tube 11, when the rotation speed of the insertion tube 11 is 10 rpm and the drawing speed is 2 minutes / m, the nozzles 14a and 15a become 20 rotations / m and become 5 cm per rotation. Will only rise.
[0041]
For this reason, if the distance between the nozzle 14a and the upper end of the stirring blade 13A is set to 2.5 cm, the injected stirring material line can be immediately stirred by the stirring blade 13B on the opposite side. Further, if the distance between the nozzle 14a and the upper end of the stirring blade 13A is set to 5 cm, the stirring blade 13A that has made another round can be stirred, and the stirring efficiency of the ground can be increased.
[0042]
Of course, in the jet agitation apparatus 10 of the present embodiment, the cross jet is formed by the jets jetted from the upper and lower jet discharge units 14 and 15, so that the solidified pile is finished by reducing the jet energy at the intersection P. The diameter can be controlled.
[0043]
By the way, the injection stirrer 10 of the present invention has been described by taking the above embodiment as an example, but it is needless to say that the present invention is not limited to this embodiment, and various embodiments can be adopted without departing from the gist of the present invention. For example, a high-pressure jet of a hardening material or the like is jetted out of one of a pair of nozzles in parallel to a horizontal plane (jet), and the hardening material is crossed from the other nozzle to the jet of one nozzle. It is needless to say that the above-described embodiment can be applied to an injection stirrer of a type that ejects a high-pressure jet such as described above.
[0044]
【The invention's effect】
As described above, according to the first aspect of the present invention, since the upper and lower stirring blades respectively cover at least the front side in the moving direction of the corresponding upper and lower jet discharge sections, when the insertion pipe is rotated. In addition, it is possible to prevent the resistance of the ground soil from directly acting on the upper and lower jet discharge sections, and it is not necessary to excessively increase the strength of the upper and lower jet discharge sections themselves and their mounting strength. It can be simplified, and the cost can be reduced accordingly.
[0045]
In addition, since the excavation wing is provided at the lowermost end of the insertion pipe, the ground can be excavated with the rotation of the insertion pipe, and the insertion pipe can be inserted into the ground, so that the pre-drilling in the previous process is performed. It is not necessary, and the work process of ground improvement can be simplified.
[0046]
According to the second aspect of the present invention, in addition to the effect of the first aspect, the upper and lower jet discharge sections are arranged in the hollow portions of the upper and lower stirring blades formed in a hollow shape, so that Not only can the resistance be prevented from acting on the jet discharge part, but also the jet immediately after jetting from the jet discharge part can be protected from the ground soil, so that the jet distance can be increased and, consequently, water or hardened material can be pumped. The size of the pump to be used can be reduced.
[0047]
According to the third aspect of the invention, in addition to the effects of the first and second aspects of the present invention, the turning radius of each of the upper and lower stirring blades is formed to be substantially the same as the turning radius of the excavating blade. When penetrating into the ground, the original ground for the radius of rotation of the excavating wings is sufficiently disturbed by the stirring blades, so that the slime can be removed by the slurry discharge at the time of drawing, and the hardened material and ground soil can be removed. Since the mixing efficiency is increased by stirring and mixing, the quality of the consolidated pile can be improved.
[Brief description of the drawings]
FIG. 1 is a sectional front view showing a monitor portion of a jet stirring device according to an embodiment of the present invention.
FIG. 2 is a side view showing a monitor portion of the jet stirring device according to the embodiment of the present invention.
FIG. 3 is an enlarged sectional view of a portion A in FIG.
FIG. 4 is an enlarged sectional view taken along line BB in FIG.
FIG. 5 is a side view of the crane to which the jet stirring device according to the embodiment of the present invention is attached.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Injection stirring apparatus 10A Monitor part 11 Insertion pipe 12 Drilling blade 13 Stirring blade 13A Upper stirring blade 13B Lower stirring blade 13Aa, 13Ba Hollow part 14 Upper jet discharge part 15 Lower jet discharge part

Claims (3)

The excavating wing provided at the lowermost end of the insertion pipe that can be raised and lowered while rotating, the stirring wing provided above the digging wing of the insertion pipe, and the injection directions intersected with each other at predetermined intervals in the vertical direction of the insertion pipe. A monitor part comprising upper and lower jet discharge sections for jetting water or hardening material so as to perform
The agitating blades are constituted by upper and lower agitating blades paired up and down corresponding to the upper and lower jet discharge portions, respectively, and the upper and lower agitating blades respectively correspond to the upper and lower jet discharging portions. An injection stirrer using a cross jet, wherein at least the front side in the moving direction is covered. The upper and lower stirring blades have a hollow shape in which a hollow portion is formed in an axial direction perpendicular to the insertion pipe, and the upper and lower jet discharge portions corresponding to the upper and lower stirring blades are disposed in the hollow portions of the upper and lower stirring blades. An injection stirrer using the cross jet according to claim 1. The jet stirring device using a cross jet according to claim 1 or 2, wherein the rotation radius of each of the upper and lower stirring blades is substantially the same as the rotation radius of the excavating blade.

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