JP3753912B2 - Ground improvement agitator with sampler - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ground improvement stirrer having an improved soil sampler that is produced when constructing an improved pillar for increasing the supporting force of the ground.
[0002]
[Prior art]
In general, when building a house on soft ground, a ground improvement method is implemented in which a plurality of improved pillars 6 as shown in FIG. Is done. Further, in order to improve the supporting force per one of the improved column bodies 6, as shown in FIG. 5 (b), an improved column body 7 with a node having a plurality of node portions 8 provided on the improved column body is formed. There is also a ground improvement method.
Since the improved columnar body 7 with the node has the node portion 8 in which the outer diameter of the improved columnar body is enlarged, the frictional force with the ground is increased as compared with the normal improved columnar body 6. For this reason, the number of the improvement pillars which should be constructed can be reduced, the length of the improvement pillars can be shortened, and the ground improvement construction method can be simplified.
[0003]
Hereinafter, the ground improvement stirrer for constructing the improved columnar body 7 with the nodes will be described.
As shown in FIG. 6, the ground improvement agitator 1 is provided on a column 3 fixed by a construction machine 2 so as to freely move up and down, and a mixer 4 produces a solidifying agent slurry in which water and a solidifying agent are kneaded. The solidifying agent slurry is pumped to the ground improvement stirrer 1 by the pump 5.
[0004]
As shown in FIG. 7, the ground improvement agitator 1 has a hollow rotary shaft 10 having a discharge port 10 a formed at the tip thereof, and a cutting tip 110 at the tip portion thereof, and the tip of the rotary shaft 10. It has a drilling head 11 provided so as not to block the discharge port 10a, a drilling tip 120 on one edge side thereof, and an inclination of a certain angle with respect to a horizontal plane near the tip of the rotary shaft 10. A pair of drilling stirring blades 12 provided opposite to each other and the rotary shaft 10 above the drilling stirring blades 12 are provided so as to face each other so as to have a certain angle of inclination with respect to the horizontal plane. The pair of suppression stirring blades 13 and the expansion blade 14 provided on the rotary shaft 10 between the drilling stirring blade 12 and the suppression stirring blade 13.
The drilling stirring blade 12 and the suppression stirring blade 13 are provided so as to protrude in a direction perpendicular to the rotating shaft 10, respectively, and the direction in which the drilling stirring blade 12 protrudes and the suppression stirring blade 13 protrudes. The direction is 90 degrees out of phase around the rotation axis 10.
[0005]
As shown in FIGS. 7 and 8, the enlarged wing 14 has a pair of brackets 40 fixed to the rotary shaft 10 at regular intervals in the vertical direction and a support pin 41 penetrating the bracket 40 as a support shaft. And a pair of enlarged arms 42 provided so as to be rotatable about an axis. The bracket 40 is provided with four restriction pins 43 for restricting the rotation of the enlargement arm 42 so as to penetrate the bracket 40.
[0006]
The expansion arm 42 is plate-shaped, and the excavation tip 420 is fixed to the tip side of the enlargement arm 42 at the side of the rotation direction at the time of reversal. Further, as shown in FIG. 8, the base end portion of the expansion arm 42 has an arcuate portion 42 a that allows the expansion arm 42 to turn without contacting the restriction pin 43 with the support pin 41 as a support shaft, A corner portion 42b that restricts the rotation of the expansion arm 42 by contacting the restriction pin 43 at a predetermined position is formed.
[0007]
Further, as shown in FIG. 7B, each of the pair of expansion arms 42 is provided with three excavation stirring pins 44. Of the three excavating agitation pins 44 provided on one of the pair of expansion arms 42 (the right hand side in the figure), the first is in the direction parallel to the rotary shaft 10 at the tip of the expansion arm 42. The second is a radial distance shorter than the radial distance between the first excavation stirring pin 44 and the rotary shaft 10, and the tip of the drilling stirring blade 12 and the rotary shaft 10 is provided at a position where the radial distance is longer than the radial distance from 10 so as to protrude downward in a direction parallel to the rotation shaft 10, and the third rotates with the second excavation stirring pin 44. A radial distance shorter than the radial distance from the shaft 10 and a radial distance longer than the radial distance between the tip of the drilling stirring blade 12 and the rotary shaft 10, in a direction parallel to the rotary shaft 10 and above. It is provided to protrude.
[0008]
Of the three excavation stirring pins 44 provided on the other (left hand side) enlargement arm 42, the first one has a direction parallel to the rotary shaft 10 at the tip of the enlargement arm 42. The second is a radial distance shorter than the radial distance between the first excavation stirring pin 44 and the rotary shaft 10, and rotates with the tip of the drilling stirring blade 12. It is provided at a position where the radial distance is longer than the radial distance from the shaft 10 so as to protrude upward in the direction parallel to the rotary shaft 10, and the third rotates with the second excavation stirring pin 44. At a position that is shorter than the radial distance from the shaft 10 and longer than the radial distance between the tip of the drilling stirring blade 12 and the rotating shaft 10, the lower side in the direction parallel to the rotating shaft 10 It is provided so as to protrude.
Accordingly, each excavation stirring pin 44 provided on the pair of expansion arms 42 is a point object with respect to the rotation center of the expansion blade 14.
[0009]
Thereby, as shown in FIG. 8 (a), when the rotary shaft 10 reverses (rotates counterclockwise), the expansion arm 42 opens in the direction in which the expansion arm 42 opens due to the resistance of centrifugal force and earth and sand. To turn. The enlargement arm 42 has its tip portion farthest from the rotary shaft 10 and the corner portion 42b abuts against the restriction pin 43 so that the rotation is restricted. It becomes larger than the rotating outer diameter of the stirring blade 13. On the other hand, as shown in FIG. 8B, when the rotary shaft 10 rotates in the forward direction (clockwise rotation), it rotates until the side portion of the expansion arm 42 abuts against the regulation pin 43 due to resistance of earth and sand. As a result, the rotating outer diameter of the expanding blade 14 becomes equal to the rotating outer diameter of the drilling stirring blade 12 or the suppression stirring blade 13.
[0010]
Next, a method for constructing the improved columnar body 7 with a node in the ground using the ground improvement stirrer 1 will be described with reference to FIG.
First, after positioning the ground improvement stirrer 1, the rotating shaft 10 is rotated forward, and the ground is dug by the drilling head 11 and the drilling stirring blade 12 (FIG. 9 (a)). At this time, the expansion arm 42 of the expansion blade 14 is in a state of being accommodated within the outer diameter of the drilling stirring blade 12 as shown in FIG. And after the front-end | tip of the ground improvement stirrer 1 reaches the set depth, the solidifying agent slurry is pumped into the rotating shaft 10 of the ground improving stirrer 1 by the pump 5, and the solidifying agent slurry is transferred to the rotating shaft 10. While discharging from the discharge port 10a, the ground improvement stirrer 1 is pulled up while the rotating shaft 10 is rotated forward. Thereby, the drilling stirring blade 12 and the suppression stirring blade 13 mix and stir the earth and sand and the solidifying agent slurry (FIG. 9B).
[0011]
After finishing the mixing and stirring of the earth and sand and the solidifying agent slurry, the rotating shaft 10 is reversed at an arbitrary depth. As a result, as shown in FIG. 8 (a), the enlarged arm 42 of the enlarged blade 14 has a tip portion that exceeds the rotational outer diameter of the drilling stirring blade 12 and has a larger outer diameter portion than when the hollow portion is dug first. The earth and sand are excavated, and the earth and sand and the solidifying agent slurry are mixed and stirred. In this state, the ground improvement stirrer 1 is moved up and down by the width of the node to be formed to form a node on the improved column to be constructed (FIG. 9 (c)). Thereafter, the rotating shaft 10 is rotated forward so that the expanding arm 42 is rotated to a state where it can be accommodated within the rotating outer diameter of the hole agitating blade 12 and pulled up to a predetermined depth, and then the rotating shaft 10 is reversed again. In the same manner as described above, a new node is formed in the improved pillar to be constructed (FIG. 9 (d)). Again, the rotating shaft 10 is rotated forward to rotate the expanding arm 42 so that it is within the rotating outer diameter of the drilling stirring blade 12, and then pulled up to a predetermined depth (FIG. 9 (e)).
[0012]
By repeating this, an arbitrary number of nodes are formed, the rotating shaft 10 is rotated forward, and the expansion arm 42 is rotated to a state that fits within the rotating outer diameter of the drilling stirring blade 12 to improve the ground improvement stirring. The machine 1 is pulled up (FIG. 9 (f)). By repeating such a series of operations, an arbitrary number of knotted improvement pillars 7 are produced on the ground, and after a certain period of time, the solidifying agent slurry is cured and the knotted improvement pillars 7 are built.
In addition, when constructing the improved column body 6 that does not have the node portion 8, the ground excavation shown in FIG. The injection stirring shown in 9 (b) may be performed.
[0013]
[Problems to be solved by the invention]
However, since the improved pillar body 6 or the improved pillar body 7 with a knot is constructed in the ground, the operator cannot confirm whether or not the construction is performed as designed. . In addition, depending on the working environment such as the ground condition, mixing and stirring of the solidifying agent slurry and earth and sand may be insufficient, and a non-uniform improved soil may be produced. Since the worker cannot confirm the improvement, the improved soil is hardened in a non-uniform state, and as a result, the improved pillar 6 or the improved pillar 7 with a knot does not reach the set strength. The problem of not being able to demonstrate the support power of.
The present invention has been made in view of the above points, and is a means for constructing an improved pillar for increasing the supporting force of the ground and confirming whether or not the intended improved soil has been produced. The purpose is to provide.
[0014]
[Means for Solving the Problems]
A ground improvement stirrer with a sampler according to claim 1 of the present invention made to achieve the above object is a hollow rotating shaft, a drilling head provided near the tip of the rotating shaft, and the rotating shaft. A ground improvement agitator with a sampler, wherein the sampler includes a wing-like body that excavates or agitates the ground, or both, and a tubular sampler. The shaft is detachably provided at a desired position of the shaft so that the opening faces the rotation direction of the rotation shaft.
[0015]
Further, the ground improvement agitator with a sampler according to claim 2 is the ground improvement agitator with a sampler according to claim 1, wherein the sampler is formed obliquely so that the opening cross section at both ends thereof faces the rotating shaft side. It has been done.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a view for explaining a configuration of a ground improvement stirrer with a sampler according to an embodiment of the present invention, and shows a front surface and a side surface of a ground improvement stirrer 100 with a sampler.
As shown in FIG. 1, the ground improvement stirrer 100 with the sampler has the same configuration as the ground improvement stirrer 1 described above except that the sampler 15 is detachably fixed to the rotating shaft 10. That is, the ground improvement stirrer 100 with the sampler has a hollow rotary shaft 10 having a discharge port 10a formed at the tip thereof, and a cutting tip 110 at the tip portion thereof. A drilling head 11 provided so as not to block the discharge port 10a, a drilling tip 120 on one edge side thereof, and an inclination at a certain angle with respect to a horizontal plane in the vicinity of the tip of the rotary shaft 10 A pair of drilling agitating blades (wing-like bodies) 12 provided opposite to each other, and a rotary shaft 10 above the drilling stirring agitating blade 12 so as to be opposed to each other so as to have a fixed angle with respect to the horizontal plane. A pair of restrained stirring blades (wings) 13, an enlarged blade (wings) 14 provided on the rotary shaft 10 between the drilling stirring blade 12 and the restraining stirring blade 13, The opening of the rotary shaft 10 faces the rotational direction of the rotary shaft 10. It is made of detachably provided tubular sampler 15. As.
[0017]
Although not shown, the ground improvement stirrer 100 with the sampler is also provided so as to be movable up and down on the column 3 fixed by the construction machine 2 and is solidified by kneading water and a solidifying agent by the mixer 4. The agent slurry is prepared, and the solidifying agent slurry is pumped by the pump 5 to the ground improvement agitator 100 with a sampler.
[0018]
As shown in FIG. 2, the sampler 15 has a tubular shape made of carbon steel, and the openings 51 at both ends of the sampler 15 are formed obliquely so that the opening cross-sections face the rotating shaft 10 side. ing. Therefore, the sampler 15 is attached to the rotating shaft 10 so that the opening 51 faces the rotating direction of the rotating shaft 10 and the opening cross section of the opening 51 faces the rotating shaft 10 side. Further, as shown in the figure, the sampler 15 is fixed to the rotating shaft 10 by a number line 52, but is not limited to the number line 52 as long as the sampler 15 can be attached to and detached from the rotating shaft 10. For example, an appropriate metal fitting or the like along the shape of the sampler 15 may be attached to the rotary shaft 10 in advance, and the sampler 15 may be fitted to the metal fitting.
[0019]
Hereinafter, the improved soil sampling method using the ground improved stirrer 100 with the sampler will be described with reference to FIGS. 3 and 4. In FIG. 3, for the sake of convenience, the drilling stirring blade 12, the suppression stirring blade 13, the expansion blade 14 and the like are omitted.
First, using the ground improvement agitator 100 with the sampler with the sampler 15 removed, the improved columnar body 7 with a node is constructed in the same manner as described above, and immediately after that, that is, before the improved soil is hardened. The sampler 15 is attached to the rotating shaft 10 using the wire 52 (FIG. 3 (a)).
[0020]
Next, the ground improvement stirrer 100 with a sampler is pushed into the improved columnar body 7 with a node in a non-rotating state (FIG. 3 (b)). At this time, since the opening 51 of the sampler 15 is horizontal and stationary, the improved soil hardly enters the sampler 15.
[0021]
Then, until the sampler 15 of the ground improvement agitator 100 with the sampler reaches the layer to be sampled, the ground improvement agitator 100 with the sampler is pushed into the improved columnar body 7 with the node, and the sampler 15 is the layer to be sampled. Is reached, the rotating shaft 10 is rotated several times in the forward rotation direction (FIG. 3 (c)). As a result, the improved soil in the shaded area in FIG. 4 is filled into the sampler 15 from the opening 51 of the sampler 15.
[0022]
Note that it is desirable to slowly rotate the rotary shaft 10 in order to reliably fill the improved soil in the sampler 15. Further, even when improved soil other than the layer to be sampled enters the sampler 15 of the ground improved stirrer 100 with the sampler during the indentation shown in FIG. The improved soil is discharged from the sampler 15 by rotating the shaft 10 several times in the forward rotation direction.
[0023]
Thereafter, the ground improvement stirrer 100 with the sampler is slowly pulled up in a non-rotating state (FIG. 5 (d)). As a result, the sampler 15 is pulled up with the improved soil in the layer to be sampled filled therein. And if the ground improvement stirrer 100 with a sampler is pulled up completely, the sampler 15 will be removed from the rotating shaft 10. Then, the necessary soil test is performed such as taking out the improved soil filled in the sampler 15 from the sampler 15 and confirming the state of the improved soil. At this time, when the ground improvement stirrer 100 with the sampler is pulled up around the opening 51 of the sampler 15, since the improved soil of the layer that is not the sampling target adheres, the test is performed after removing the improved soil around the opening 51. It is desirable to do. Thereby, it can be confirmed whether or not the improved soil of the knotted improved column 7 is of a good quality, that is, whether or not the mixing and stirring of the solidifying agent slurry and the earth and sand have been sufficiently performed. As a result, if a non-uniform improved soil is produced, the ground improvement method is applied again.
[0024]
In addition, after completion | finish of sampling, the improvement soil of the improvement pillar body 7 with a node disturbed by sampling will be repaired by stirring again using the ground improvement stirrer 100 with a sampler.
In addition, even when the improved column 6 having no node is constructed, sampling can be performed by the same method as described above.
[0025]
Thus, according to the ground improvement stirrer 100 with the sampler according to the present embodiment, the tubular sampler 15 is detachably fixed to the rotating shaft 10 so that the opening 51 faces the rotating direction of the rotating shaft 10. Therefore, after constructing the improved pillar body 7 with a node in the ground, the improved soil of a desired layer is sampled, and whether or not the improved soil is of high quality, that is, the solidifying agent slurry and the earth and sand It can be confirmed whether mixing and stirring are sufficiently performed.
[0026]
Further, the openings 51 at both ends of the sampler 15 are formed obliquely so that the opening cross section faces the rotating shaft 10 side, and the sampler 15 is arranged so that the opening 51 faces the rotation direction of the rotating shaft 10; Since the opening cross section of the opening 51 is attached to the rotating shaft 10 so as to face the rotating shaft 10 side, it is possible to efficiently sample the improved soil in a desired layer of the knotted improved column 7.
[0027]
In the present embodiment, the ground improvement stirrer 100 with the sampler is provided with the expansion blades 14. However, in the case of constructing the improved column body 6 without the node portion 8, the expansion blades 14 are provided. The one not provided, that is, the one whose rotation outer diameter is not enlarged is used.
In the present embodiment, the sampler 15 is a straight tubular body. However, the sampler 15 may be bent according to the shape of the rotating shaft 10 and the rotating direction, for example, a U-shaped tubular body.
In the present embodiment, the sampler 15 is attached near the upper part of the stirring blade 14 of the rotating shaft 10. However, for the convenience of the depth of the layer to be sampled and attachment / detachment work, the sampler 15 You may change an attachment position to the downward direction of the stirring blade 14, etc., for example.
[0028]
Further, if a cover that can be opened and closed only at the outer opening is provided in the opening 51 on the side in the rotation direction when the rotation shaft 10 is rotated forward among the openings 51 of the sampler 15, the rotation shaft in the improved soil is provided. Even if 10 is rotated forward, the inside of the sampler 15 is not filled with the improved soil by the lid, and if the rotating shaft 10 is reversed, the lid is opened to the outside by the pressure of the improved soil, and the interior of the sampler 15 is improved. The soil will be filled. Thus, the ground improvement agitator with a sampler 100 is pushed into the improved column 6 while rotating forward, the rotating shaft 10 is reversed at a desired position, and the improved soil to be sampled is filled into the sampler 15. Therefore, it is possible to easily push and pull up the ground improvement stirrer with sampler 100 during sampling.
[0029]
【The invention's effect】
As described above, according to the ground improvement agitator with a sampler according to the present invention, the hollow rotating shaft, the drilling head provided near the tip of the rotating shaft, and the rotating shaft at regular intervals. A ground improvement stirrer with a sampler comprising a plurality of projecting wings that excavate or stir the ground or both, and a tubular sampler, wherein the sampler is at a desired position of the rotating shaft. In addition, since the opening is provided so as to be detachable so as to face the rotation direction of the rotating shaft, improvement of a desired layer is made after constructing the improved column body or the improved column body with a node in the ground. By sampling the soil, it can be confirmed whether or not the improved soil is of good quality, that is, whether or not the mixing and stirring of the solidifying agent slurry and the earth and sand have been sufficiently performed. As a result, in the case where non-uniform improved soil is produced, the improved column body does not reach the set strength by repairing by stirring the improved soil again, etc. It can be prevented that the supporting force cannot be exhibited.
[0030]
Further, according to the present invention, the sampler is formed obliquely so that the opening cross-sections at both ends thereof face the rotating shaft side, so that the sampler can be formed in a desired layer of the improved column body or the improved column body with a node. Sampling of some improved soil can be performed efficiently.
[Brief description of the drawings]
1A and 1B are a front view and a side view showing a configuration of a ground improvement stirrer with a sampler according to an embodiment of the present invention.
FIG. 2 is a schematic perspective view showing a configuration of a sampler 15. FIG.
FIG. 3 is a schematic diagram for explaining a sampling method using a ground improvement stirrer with a sampler 100. FIG.
FIG. 4 is a plan view showing an area of improved soil sampled by a sampler 15;
FIG. 5 is a schematic view showing an improved column body 6 and a knotted improved column body 7 for increasing the supporting force of the ground.
FIG. 6 is a schematic view showing an apparatus used for the ground improvement method.
FIG. 7 is a front view and a side view showing a configuration of a conventional ground improvement stirrer 1.
FIG. 8 is a plan view showing a state of the expanding blade 14 at the time of normal rotation and reverse.
FIG. 9 is a schematic diagram for explaining a method for constructing a knotted improved column 7 using a conventional ground improved stirrer 1;
[Explanation of symbols]
10 Rotating shaft 100 Ground improvement stirrer 11 Drilling head 12 Drilling stirring blade (wing-shaped body)
13 Suppressing stirring blade (winged body)
14 Expanded wings (wings)
15 Sampler 51 Opening 6 Improved column 7 Improved column with knot

Claims (2)

A hollow rotary shaft, a drilling head provided near the tip of the rotary shaft, and a plurality of wings that project from the rotary shaft at regular intervals and excavate or agitate the ground. A ground improvement stirrer with a sampler comprising a tubular sampler,
A ground improved agitator with a sampler, wherein the sampler is detachably provided at a desired position of the rotating shaft so that its opening faces the rotating direction of the rotating shaft. The ground improvement stirrer with a sampler according to claim 1, wherein the sampler is formed obliquely so that opening cross sections at both ends thereof face the rotation axis side.

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