KR100523416B1 - Agitating device for ground improvement and hammer bit - Google Patents

Abstract

The present invention relates to a ground improvement agitator capable of producing an improved body by stirring and mixing the improved material and the soil to be improved by crushing and excavating a rock layer such as weathered rock, soft rock, and granite, or a rock layer such as amber stone. The present invention relates to an auger shaft provided with a cylindrical receiving part having an open lower portion at a lower end thereof, an agitating wing provided at a middle portion of an outer circumferential surface of the auger shaft, an excavation wing provided at a lower end of the outer circumferential surface of the auger shaft, and rotating in conjunction with the auger shaft. A hammer bit coupled to the receiving portion so as to reciprocate along an axial direction of an auger shaft, a strike means provided on the receiving portion to strike the upper surface of the hammer bit, and an improved material to induce a reciprocating movement of the hammer bit. Is formed in the auger shaft to be supplied along the axial direction of the auger shaft to be ejected from the lower portion of the auger shaft In the ground improvement stirring device comprising an improved material supply passage: the lower portion of the hammer bit is in the form of a column in a substantially columnar shape along the axial direction of the hammer bit and the central portion at equal intervals around the central portion It is characterized by consisting of a plurality of extended legs arranged.

Description

AGITTING DEVICE FOR GROUND IMPROVEMENT AND HAMMER BIT}

The present invention relates to an agitator for improving soil, and includes an improved body in which rock and rock layers, such as weathered rock, soft rock, and granite, and a stone layer such as amber stones are crushed and excavated in the ground to be improved, and the mixed material is stirred and mixed with the ground to be improved. It relates to a ground improvement stirring device that can be made.

In general, the ground improvement agitator is used in the deep mixing treatment method, the deep mixing treatment method is a deep in the field to improve the properties of the soil such as cement, bentonite, lime, solids, slag, or microorganisms in the soil, The improved material that can be solidified or processed is mixed with soil while being introduced into the ground at low pressure by using a special equipment (Multi-Shaft Auger Machine) that can rotate 1 to 3 axes of auger shafts with agitator blades. It refers to the continuous improvement method for underground, which causes physical and chemical changes such as an increase in water content, a decrease in water content, an increase in binding strength, and microbial treatment, to increase water-order and compressive strength, and to prevent contamination.

1 is a view of an embodiment using the conventional deep mixing treatment method described above. As shown in the drawing, the conventional construction method is used for constructing continuous continuous walls such as soft ground reinforcement, earth walls of underground trenches, and water walls of river banks.In the ground environment field, the movement of contaminated groundwater such as unsanitary landfills and waste mines is blocked. It is used as a shielding wall or to stabilize or fix contaminated soil to prevent the diffusion of heavy metals or semi-volatile organic compounds, and is also used for biological treatment of contaminated soil by mixing with microorganisms and adding it to the ground. It is also used to create permeable walls that have the function of purifying contaminated groundwater by injecting light.

In general, the ground agitating device for digging the ground should be dug into the ground to the depth desired by the auger, for this purpose is provided with excavation wings at the tip of the auger.

As a conventional technique in which such excavation wings have been described, Japanese Laid-Open Patent Publication No. Hei 1-219210, "Soft ground improvement device" incorporated in the present specification is known.

However, in the case of excavation using only the excavation wing as described above, the excavation is easily performed in the case of the soft ground, but if the rock layer or the gypsum layer is present in the ground to be improved, mechanical damage occurs rather frequently.

Korean Utility Model Registration No. 20-0317286 "Ground Improvement Stirring Device" incorporated in the present specification as a conventional technology has a structure in which a pneumatic drilling hammer is adopted at the bottom of the auger shaft together with the excavation wing for crushing and excavating the rock layer or the stone layer. Is showing.

In the above-mentioned excavation hammer, the upper surface is hit by a piston reciprocating up and down by pneumatic pressure, and comprises a hammer bit hitting a rock layer or the like by a plurality of protrusions provided on the lower surface by the piston strike.

In addition, since the hammer bit is splined to the auger shaft, the hammer bit is moved up and down by the stroke of the piston and simultaneously rotates with the auger shaft.

According to the prior art as described above, the hammer bit of the drilling hammer has a cylindrical shape at the bottom thereof, and thus the fracture surface of the ground crushed by the hammer bit has a circular shape, and the rotation radius of the hammer bit is excavated. It was made smaller than the rotation radius of the blade. If the rotation radius of the hammer bit is generally coincident with the rotation radius of the excavation blade, this results in the diameter of the drilling hole and the diameter of the hammer bit almost coincident, and as a result, the slime due to the pressure of the hammer bit when the auger shaft is pulled out. This is because an overflow of slime occurs.

Due to this problem, when the rotation radius of the hammer bit of the drilling hammer is smaller than the rotation radius of the drilling blade as in the related art, the rock layer fractured by the hammer bit is smaller than the diameter of the drilling hole as shown in FIG. Therefore, the part located at the outer part of the crushing surface fractured by the hammer bit should still be excavated only by the excavation wing.

In other words, if the rock layer exists outside the crushing range of the hammer bit or if the rock layer is located over the entire surface of the excavation site, it will not be excavated or damage the machine.

It is an object of the present invention to focus on the conventional problems as described above, so that the crushing range by the hammer bit is generally coincident with the diameter of the excavation hole to efficiently carry out excavation work of the ground improvement stirring device.

In addition, an object of the present invention is to prevent the slime overflow due to the ground improvement stirring device while the crushing range by the hammer bit generally coincides with the diameter of the drilling hole.

In addition, an object of the present invention is to maximize the crushing function of the ground improvement stirring device by narrowing the area of the rock layer to be hit even by the hammer bit reciprocating by the same stroke, thereby increasing the impact received by the rock layer .

In order to achieve the above object, the present invention, in order to improve the ground, the auger shaft is provided with a cylindrical receiving portion is opened at the lower end, the stirring blade provided in the middle portion of the outer peripheral surface of the auger shaft, the lower end of the outer peripheral surface of the auger shaft Excavating wing is provided, the hammer bit coupled to the receiving portion to reciprocate along the axial direction of the auger shaft while rotating in conjunction with the auger shaft, provided in the receiving portion to cause the reciprocating movement of the hammer bit A striking means for striking the upper surface of the bit, and an improved material supply path formed in the auger shaft so that the improved material is supplied along the axial direction of the auger shaft and ejected from the lower portion of the auger shaft. The bottom of the hammer bit is generally columnar along the axial direction of the hammer bit. Is composed of a plurality of extension legs that are spoken with the center and the center and are arranged at equal intervals around the center, the diameter of the center of the hammer bit is the same or smaller than the outer diameter of the auger shaft, the plurality of extension legs It is characterized in that the diameter of the circular surface formed by the rotation of the ends of the plurality of extension legs is formed larger than the outer diameter of the auger shaft.

In the above, it is preferable that the length of the extension leg is made so that the rotation radius formed by the end of the extension leg substantially coincides with the rotation radius formed by the excavating wing.

As a result, the crushing range by the hammer bit generally coincides with the diameter of the excavation hole, so that efficient excavation work of the ground improvement stirring device is possible.

In the above, it is preferable that the number of the said extension legs is 2 or more and 4 or less.

The extension leg should be more than a certain cross-sectional area in order to have a certain degree of impact resistance to withstand hitting the rock layer. Therefore, if the number of extension legs is 5 or more, the area occupied by the hammer bit is excessively increased and slimes. This is because an overflow of may occur.

In the above, it is preferable that an arc-shaped resistance attenuation surface is formed on the side of the extended leg distal end.

The hammer bit rotates in conjunction with the rotation of the auger shaft, so that the extension leg that is part of the hammer bit also rotates together.

When the extension legs are rotated in this way, the rotation direction side of the extension legs (the surface of the extension legs pushing the soil around the axis) is subjected to the pressure of the soil, which is maximized at the distal end of the extension bridge. Therefore, it is preferable to form an arc-shaped resistance attenuation surface on the rotational side of the extended leg distal end to prevent breakage of the extended leg due to the pressure of the soil.

In the above, it is preferable that the drilling bit provided in the lower portion of the drilling blade is located in the upper center of the adjacent between the extension legs.

In order to avoid the excavation bit provided on the excavation wing to interfere with the extension leg, it is preferable to configure the extension leg and the excavation bit alternately, and the excavation wing first excavates the fractured rock at the lower part of the extension leg. Excavation work can be carried out more easily.

In the above, the lower end of the auger shaft is provided with a reinforcement cover is in communication with the receiving portion and engaged with the center and the upper surface of the extension leg is provided, the lower portion of the hammer bit in the lower portion of the reinforcement cover It is desirable to provide breakage preventing means for preventing. Reinforcing pieces or reinforcing bands to be described later may be mentioned as the damage preventing means. In another aspect of the present invention, in the hammer bit reciprocally coupled to the auger shaft of the ground improvement stirring device, The lower portion is composed of a central portion having a generally columnar shape along the axial direction of the hammer bit and a plurality of extension bridges arranged at equal intervals about the central portion, and the diameter of the central portion of the hammer bit is the auger. It is the same or smaller than the outer diameter of the shaft, wherein the plurality of extension legs is characterized in that the diameter of the circular surface formed by the rotation of the ends of the plurality of extension legs is formed larger than the outer diameter of the auger shaft.

Hereinafter, the configuration and operation of the present invention according to the embodiment of the present invention will be described in detail.

FIG. 3 is a front view of the first embodiment according to the present invention, and FIG. 4 is a bottom view of only the hammer bit and the drilling bit viewed from the bottom in order to show the planar position of the hammer bit and the drilling bit of FIG.

The stirring blade (not shown) is provided in the middle part of the outer peripheral surface of the auger shaft 10, and the excavation blade 20 is provided in the lower peripheral surface of the auger shaft 10. As shown in FIG.

In the lower part of the excavation wing 20, an excavation bit 21 is provided for ground excavation.

Therefore, the stirring blade and the excavation blade 20 provided on the outer circumferential surface of the auger shaft 10 together with the rotation of the auger shaft 10 rotate together.

The shape of the stirring blade and the excavation wing 20 can be variously modified and various forms have already been proposed as a conventional technology.

The lower end of the auger shaft 10 is provided with a cylindrical accommodating portion 11 having a lower opening, and a hammer bit 30 is coupled to the accommodating portion 11.

The hammer bit 30 is coupled to the receiving portion 11 so as to reciprocate along the axial direction of the auger shaft 10 while rotating in conjunction with the auger shaft 10, this coupling method is to the first rotary shaft and the first rotary shaft Inserted and rotated together, but belongs to a well-known technique known to be related to the axial coupling consisting of a second rotary shaft reciprocating in the axial direction of the first rotary shaft, it can be implemented by spline coupling, key coupling and the like.

The accommodating part 11 is provided with a striking means (not shown) for injecting a hammer on the upper surface of the hammer bit 30 to cause the hammer bit 30 to reciprocate.

As a general hitting means is known a pneumatic method, a hydraulic method, an electric method.

Hereinafter, the operation principle of the hitting means by the pneumatic method and the hydraulic method will be briefly described as the typical hitting means.

In case of pneumatic type, compressed air by compressor is required.When the compressed air flows into the piston, the piston moves forward along the cylinder, hitting the hammer bit, and when the compressed air is blown out through the hammer bit, The piston is repeatedly operated to retreat upward by the repulsive force.

Therefore, in case of pneumatic method, air discharge hole should be provided in hammer bit to secure the discharge passage of compressed air.

On the other hand, in the hydraulic system, when a high pressure fluid is supplied to the first pressure chamber under the piston, the piston retreats upward by the high pressure fluid, whereby the piston compresses the gas filled in the gas chamber provided at the upper At the same time as the top dead center of the piston is reached, the valve is switched to supply the high pressure fluid to the second pressure chamber formed at the upper portion of the piston, and by this operation, the pressure by the first pressure chamber is canceled by the second pressure chamber. Therefore, the filling gas compressed by the piston expands and the piston advances downward with its expansion force to strike the hammer bit.

Therefore, in the case of the hydraulic method, the hammer bit does not need to be provided with an air discharge hole, which is a discharge passage of the compressed air, which is required by the blow means by the pneumatic method.

However, in the case of the hammer bit may be provided with an air discharge hole, if necessary, even in the case of a hydraulic hitting means. For example, when the high pressure compressed air is injected toward the ground for splitting of the ground, an air discharge hole may be separately provided.

An improved material supply path (not shown) is formed in the auger shaft 10 so that the improved material is supplied along the axial direction of the auger shaft 10 and ejected from the lower part of the auger shaft 10.

The structure of the improved material supply passage is already well known in various ways. For example, there may be mentioned a method of ejecting downward from the lower part of the auger shaft, or connected to the excavation wing to eject downward from the bottom of the excavation wing, or radially ejecting from the lower part of the auger shaft.

As mentioned above, various materials are used as mentioned above and are still being developed.

The lower portion of the hammer bit 30 is composed of a central portion 31 and two extension legs (32).

The upper portion of the hammer bit 30 rotates together with the auger shaft 10 and is reciprocally accommodated along the axial direction of the auger shaft 10 in the accommodating portion 10 by the striking means provided in the accommodating portion 11. In combination with the part 10, the central part 31 is spoken with the upper part of the hammer bit, and the extension leg 32 is spoken with the central part 31.

In addition, the extension legs 32 are arranged at equal intervals around the central portion 31, and in the present embodiment, are disposed at 180 ° intervals.

The lower surface of the central portion 31 and the extension leg 32 is provided with a plurality of protrusions 33 for fracture of the rock layer or the like as is conventionally implemented in the prior art. The arrangement of the plurality of protrusions 33 provided on the lower surface of the central portion 31 and the extension leg 32 is known in various forms.

The length of the extension leg 32 is formed such that the rotation radius formed by the end of the extension leg 32 substantially coincides with the rotation radius formed by the excavation wing 20. That is, the crushed surface that is broken while the extension leg 32 and the central portion 31 are rotated together with the auger shaft 10 and moved up and down by the striking means almost coincides with the excavated surface excavated by the excavation wing 20. .

In addition, an arc-shaped resistance damping surface 32a is formed on the rotational side of the distal end of the extended leg 32.

Excavation bit 21 provided in the lower portion of the excavation wing 20 is located at the upper center of the center between the adjacent extension legs. In order to avoid mutual interference between the excavation bit 21 and the extension leg 32, the extension leg 32 and the excavation bit 21 are staggered, and the rock fractured at the lower portion of the extension leg 32 is immediately excavated. Since it meets the wing 20, the excavation of the ground becomes easier.

According to the present invention, the lower portion of the hammer bit 30 is formed of the central portion 31 and the plurality of extension legs 32 extending therefrom, thereby increasing the crushing impact on the crushed surface to increase the crushing efficiency. .

This effect can be explained more simply by comparing the case where the same crushing surface is broken by a hammer bit having a simple circular cross section and the case where the crushing is made by a hammer bit consisting of a plurality of extension legs and a central part.

In other words, when the hammer bit is hit by the same hitting means, the smaller the fracture area of the hammer bit is, the better the impact of breaking is. The hammer bit having a plurality of extended legs compared to the hammer bit of the circular section has the fracture area. small. Therefore, in the case of the hammer bit provided with an extension leg, the fracture impact is superior to that of the round hammer bit.

In addition, although the hammer bit provided with a plurality of extension legs has a small fracture area by one stroke, the hammer bit rotates together with the auger shaft and performs a continuous fracture operation to finally achieve a circular fracture surface.

In addition, the lower portion of the hammer bit 30 is composed of a central portion 30 and a plurality of extension legs 32 extending therefrom, so that when the auger shaft 10 is drawn out, the slime is formed between the extension legs 32. By flowing down, the slime does not overflow.

5 is a bottom view of a hammer bit provided with four extension legs as a second embodiment according to the present invention. Therefore, the extended legs are arranged at 90 ° intervals.

6 is a bottom view of a hammer bit provided with two extension legs as a third embodiment according to the present invention. Arrows of Figure 6 indicate the direction of rotation of the extension leg.

In the present embodiment, the resistance attenuation surface 32a in the shape of an arc is formed on the rotational side of the distal end of the extended leg 32, whereas the tail 32b protrudes on the opposite side of the rotational direction of the distal end of the extended leg 32, thereby resisting. The cross-sectional area reduction caused by the attenuation surface 32a can be canceled out.

7 is a fourth embodiment according to the present invention, which is a front view of a lower hammer bit provided with two extension legs, and FIG. 8 is a bottom view of FIG.

9 is a front view of a lower portion of the hammer bit provided with two extended legs as a fifth embodiment according to the present invention.

In the present embodiment, two hemispherical extension legs 32 are provided on the side wall of the central portion 31 with different heights. By making the extension leg 32 have a hemispherical shape, the engagement area between the extension leg 32 and the central portion 31 can be widened to prevent the engagement end face from being damaged by the impact.

10 is a sixth embodiment according to the present invention, which is a front view of a hammer bit and two auger shafts provided with two extension legs, and FIG. 11 is a cross-sectional view taken along the line A-A of FIG.

In the present embodiment, the lower portion of the hammer bit is composed of a central portion 31 and two extension legs 32.

On the other hand, the lower end of the auger shaft is provided with a reinforcing cover 11 in which two reinforcing pieces 12 are formed. The reinforcing piece 12 is provided near the opposite end of rotation of the extended leg 32 in order to minimize the moment of rotation on the lower portion of the hammer bit. Therefore, the rotation moment generated due to the pressure applied by the soil to the extension leg 32 is offset by the reinforcing piece 12 formed in the reinforcing cover 11, so that the neck of the hammer bit is damaged by the rotation moment in the upper part of the central part 31. Can be prevented. In addition, in order to prevent the hammer bit neck from being damaged, a reinforcing jaw 34 having a wider cross-sectional area is formed above the center of the hammer bit. On the other hand, the inner center of the reinforcement cover 11 provided at the lower end of the auger shaft is in communication with the receiving portion such that the hammer bit is coupled to the receiving portion, and the inside of the reinforcing cover 11 is engaged with the reinforcing jaw 34 of the lower hammer bit. The space part is formed inward so that it may fall.

The arrow in FIG. 11 indicates the auger axis, that is, the rotation direction of the hammer bit.

12 is a seventh embodiment according to the present invention, which is a front view of a hammer bit and two auger shafts provided with two extension legs, and FIG. 13 is a bottom view of FIG.

In the case of this embodiment, it is similar to the structure of the sixth embodiment, and therefore, description will be mainly given of differences from the sixth embodiment.

In the present embodiment, the center portion 31 has a cylindrical shape, and the diameter of the cylinder is longer than the width of the extension leg 32.

In addition, in the present embodiment, the central portion 31 protrudes downward compared to the extension leg 32 so as to first crush the lower rock layer in the central portion 31 and then to crush the rock layer around the extension leg 32, An attempt was made to minimize the load on the extended leg 32.

FIG. 14 is a half sectional view showing a hammer bit provided with two extension legs and a lower end of an auger shaft according to an eighth embodiment of the present invention. FIG. 15 is a bottom view of FIG.

In the case of this embodiment, it is similar to the structure of the sixth embodiment, and therefore, description will be mainly given of differences from the sixth embodiment.

In the present embodiment, the structure of the reinforcing cover 11 is similar to the sixth embodiment, but in the present embodiment is formed along the circumference of the side wall of the center 31 and the extension leg 32 instead of the reinforcing piece 12, the reinforcing cover On the outer circumferential surface of (11) there is provided a reinforcing band 13 extending downward. Therefore, in the case of the reinforcing band 13, the hammer bit neck is less likely to be damaged than the reinforcing piece 12 of the sixth embodiment.

In addition, in the present embodiment, the bit 14 is provided in the reinforcing strip 13 on the side of the auger shaft rotation direction so that the ground soil can be broken.

In addition, in the present embodiment, the side wall fracture bit 35 is provided along the side wall circumference of the center 31 and the extension leg 32 so that the rock layer fracture action is also performed at the side wall of the shanghai simultaneous center 31 and the extension leg 32 of the hammer bit. Will occur.

The above embodiments only belong to preferred embodiments of the present invention, and the scope of the present invention is not limited to the above embodiments. The present invention can be variously modified or adjusted by those skilled in the art to which the present invention pertains. If such a modified or adjusted uses the technical idea of the present invention, it is within the scope of the present invention.

Therefore, in the present invention, the crushing range by the hammer bit generally coincides with the diameter of the excavation hole, so that the excavation work of the excavation blade of the stirring device for improving soil can be efficiently performed.

In addition, the present invention by placing a plurality of extension legs in the hammer bit so that the slime can be discharged between the extension legs, while performing the excavation work of the excavation wing as described above, at the same time can prevent the slime overflow due to the hammer bit. have.

In addition, the present invention, even by the hammer bit reciprocating by the same strike, by narrowing the area of the rock layer to be hit by this can increase the impact received by the rock layer can be maximized the crushing function of the ground improvement stirring device.

1 is an embodiment using a conventional deep mixing treatment method,

Figure 2 is a schematic diagram of excavation by a hammer bit,

3 is a front view of a first embodiment according to the present invention;

4 is a bottom view of a main part of FIG. 3;

5 is a bottom view of a hammer bit as a second embodiment according to the present invention;

6 is a bottom view of a hammer bit as a third embodiment according to the present invention;

7 is a fourth embodiment according to the present invention, a front view of a lower hammer bit provided with two extension legs,

8 is a bottom view of FIG. 7;

9 is a fifth embodiment according to the present invention, the front view of the lower portion of the hammer bit provided with two extension legs,

10 is a sixth embodiment according to the present invention, a front view of the hammer bit and the auger shaft bottom provided with two extension legs,

11 is a cross-sectional view taken along the line A-A of FIG.

12 is a seventh embodiment according to the present invention, a front view of a hammer bit and an auger shaft bottom provided with two extension legs;

FIG. 13 is a bottom view of FIG. 12; FIG.

14 is a half cross-sectional view of the lower end of the hammer bit and the auger shaft provided with two extension legs as an eighth embodiment according to the present invention;

15 is a bottom view of FIG. 14;

<Description of Symbols for Main Parts of Drawings>

10: auger shaft 11: receiving portion

20: excavation wing 21: excavation bit

30: hammer bit 31: center

32: extended leg 32a: resistance attenuation surface

33: turning

Claims (5)

In order to improve the ground, the auger shaft is provided with a cylindrical receiving portion is opened at the lower end, the stirring blade provided in the middle portion of the outer peripheral surface of the auger shaft, the excavating wing provided in the lower peripheral surface of the auger shaft, in conjunction with the auger shaft A hammer bit coupled to the receiving part to be reciprocally movable along the axial direction of the auger shaft while being rotated, a striking means provided to the receiving part to strike the upper surface of the hammer bit to induce a reciprocating movement of the hammer bit, and In the ground improvement stirring device comprising an improved material supply path formed in the auger shaft so that the improved material is supplied along the axial direction of the auger shaft and ejected from the lower portion of the auger shaft: The lower portion of the hammer bit is made up of a plurality of extension legs which are arranged at equal intervals around the central portion of the central portion forming a generally columnar shape along the axial direction of the hammer bit and the central portion, The diameter of the central portion of the hammer bit is equal to or smaller than the outer diameter of the auger shaft, The plurality of extension legs is a ground improvement stirring device, characterized in that the diameter of the circular surface formed by the rotation of the ends of the plurality of extension legs is formed larger than the outer diameter of the auger shaft. The ground improvement stirring apparatus according to claim 1, wherein the length of the extension leg is made to substantially coincide with the rotation radius formed by the end of the extension leg. The stirring device for ground improvement according to claim 1, wherein the number of said extension legs is 2 or more and 4 or less. In the hammer bit reciprocally coupled to the auger shaft of the ground improvement stirring device, The lower portion of the hammer bit is made up of a plurality of extension legs which are arranged at equal intervals around the central portion of the central portion forming a generally columnar shape along the axial direction of the hammer bit and the central portion, The diameter of the central portion of the hammer bit is equal to or smaller than the outer diameter of the auger shaft, And said plurality of extension legs are formed such that the diameter of the circular surface formed by the rotation of the ends of the plurality of extension legs is larger than the outer diameter of the auger shaft. The hammer bit for ground improved stirring apparatus of Claim 4 whose number of the said extension legs is 2 or more and 4 or less.