JPH07122266B2 - Improvement method of foundation ground and its drilling equipment. - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for improving a foundation ground for digging a foundation ground such as construction very easily and surely and for constructing a strong foundation layer on the foundation ground, and a drilling apparatus therefor. It is a thing.

[0002]

2. Description of the Related Art Conventionally, various ground hole drilling devices have been developed as a method for constructing a foundation ground for construction and the like, but most of them are drilled vertically in the ground with a conical earth auger. After that, however, a pile pillar was placed in the hole to be constructed. Further, a means for forming a bulb portion having a large bulb in the part of the bottom of the hole in a part thereof and filling a consolidating material such as mortar in the bulb to construct a strong ground layer in the ground is also widely known. ing. However, as described above, in the case of a means for excavating a ground layer of a considerable depth to form a hole in a bulb, for example, a tip cutting blade of an auger head is expanded to a diameter larger than the width of the auger head to form a rotary hole. Although a device has been developed, the device causes a considerably large load on the cutting blade at the time of the rotary drilling, and the breakage rate of the cutting blade as well as the failure rate are large.
There is also known a method of exploding the ground with explosives to form cavities on the bottom of the earth, but such a method causes pollution problems such as vibration and noise in the surroundings, and especially when working with the use of explosives,
There is a risk that in a soft ground layer, the explosion direction is not constant and the bulb hole that can be formed is distorted, so that a reliable bulb mass cannot be formed.

[0003]

SUMMARY OF THE INVENTION The present invention is intended to fundamentally solve the above-mentioned drawbacks, and no matter how soft and soft ground conditions are, the noise can be applied to a predetermined foundation ground without noise. Its main purpose is to build a large bulb easily and surely and to build a stronger ground surely and easily.

[0004]

As a means for achieving the above-mentioned object, the present invention has a tip 1 having a digging blade 4 at the lower end of a casing 1 having a spiral convex portion 2 at its peripheral portion. The drilling device A is formed by connecting the auger head 3 having the spiral wing piece 5 integrally attached to the upper part thereof so as to be bendable at a certain inclination angle, and the drilling device A is used to perform rotary drilling in the ground, and the drilling is predetermined. When the auger head 3 is reached, the auger head 3 is bent and expanded to a required hole diameter a width, and the auger head 3 is bent and expanded to rotate and excavate the ground, thereby forming a large bulb in the ground. It is a ground improvement method and a drilling device for drilling a hole b to construct a ground layer having a strong supporting force.

[0005]

Next, the construction example of the apparatus will be described. First, the apparatus is set on a pile driver and placed on a predetermined ground, and then the auger casing 1 is driven and rotated to excavate the tip of the auger head 3. At the same time as the blade 4 rotates to excavate the tip ground, the spiral wing piece 5 excavates the excavated soil to a predetermined depth while pressing and expanding the excavated soil around the hole. Thus, when the above-mentioned excavation reaches the destination layer, when the hydraulic jack 7 is operated from the ground, as shown in FIG. 1, the hydraulic jack 7 extends and the auger head 3 as a whole supports the hinge 6 at the bottom of the casing 1. As a shaft, the head portion is simultaneously rotated by the rotation of the casing 1 in the inclined body which is bent and expanded at a constant inclination angle, and a large diameter bulb hole b is bored in the ground as shown in FIG. It can be done.

By the above means, a bulb hole b having a predetermined diameter is formed in the ground.
2) After the end of FIG. 2 (2), the auger head 3 that can be expanded is returned to the original state below the casing 1 by the operation of the hydraulic jack 7, and then the setting material c such as mortar is fed from the tip of the auger head 3. The casing 1 is removed together with the auger head 3 to the ground while being injected and filled into the bulb hole b, and then the pile pillar P is inserted into the pile hole d and driven to form the pile pillar P as described above. It is possible to easily solidify a solid foundation ground in the ground as shown in Fig. (3) by solidifying with the bulb portion d to be made.

Further, when the coagulating material c such as the mortar is being filled, the filling mortar is satisfactorily disturbed and kneaded in the bulb hole b while continuing to rotate with the bent body of the head portion, and has a large diameter in the ground. The mortar bulb portion d may be formed simultaneously with the rotary drilling hole.

[0008]

Embodiments of the present invention will now be described with reference to the drawings. As a drilling device thereof, a casing 1 having a vertically long tubular shape as a whole and having an appropriate length is provided. Then, a spiral convex portion 2 having a constant diameter and width f is attached. The auger head 3 is a head formed by forming a tapered overall shape into a substantially conical shape. A tip digging blade 4 having an appropriate shape is attached to the tip of the auger head 3, and the above-mentioned casing 1 surface is provided above and below the peripheral surface of the head 1. A spiral wing piece 5 having a diameter width f of the spiral convex portion 2 and a diameter width g of substantially the same upper and lower sides is integrally formed. A part of the upper portion of the auger head 3 formed in such a shape is supported below the casing 1 by a connecting tool such as a hinge 6, and one end of the auger head 3 is provided with a telescopic device such as a hydraulic jack 7. When the hydraulic jack 7 is extended, the entire auger head 3 is mounted below the casing 1 so as to be capable of being expanded and bent at an appropriate inclination angle around the hinge 6. Incidentally, the mortar injecting pipe 8 for injecting the setting material c such as mortar into the casing 1 is provided.
Is vertically communicated with the mortar injection hole 9 opened at the tip of the auger head 3 through a flexible pipe or the like.

The present invention is a drilling apparatus A having the above structure.
And the casing 1 and the auger head 3 are used for rotary excavation to excavate the underground to excavate to a certain depth, as described in detail in the section of action. Above, stop the excavation, hydraulic jack 7
Is operated to gradually expand and bend the tip auger head 3 at a predetermined inclination angle. Thus, when the expansion bending is performed at a constant angle, the casing 1 is rotated and the auger head 3 is continuously rotated by the bent body at the same time as the casing 1 is rotated. easily drilling b,
Then, the mortar injection pipe 8 in the casing 1 is inserted into the above-mentioned drill hole bulb hole b to inject and fill the mortar injection hole 9 at the tip of the head with a condensing material c such as mortar to thereby fill the ground with the bulb portion d. Is formed, and the auger head 3 is then removed together with the casing 1 to the ground,
Before the mortar is solidified, a pile pillar P is placed in the residual hole in the hollow casing, and the pile is submerged, so that it is possible to construct a strong foundation ground which is integral with the bulb portion d in the ground.

When the coagulation material c such as the mortar is filled, the filling mortar is satisfactorily disturbed and kneaded in the bulb hole b when it is rotationally driven by the bent body of the head portion, so that the mortar is more reliable and rigid. The bulb portion d can be easily formed.

[0011]

As described above, according to the present invention, the casing 1 is provided with the auger head 3 having the tip 4 of a suitable shape at the tip and the spiral blade 5 integrally attached to the upper portion thereof.
Since it is connected to the lower part of the ground so that it can be expanded and bent freely at a constant inclination angle, it is extremely reliable and easy to form a bulb hole b of a required diameter regardless of the ground or depth. Can be done. Therefore, as a conventional means for forming the above-mentioned bulb portion, there is no concern about vibration, danger, etc. due to the use of explosive, as well as collapse of the borehole wall, and a safe and reliable large-sized bulb portion d can be easily formed. Since the auger head 3 part is mounted so that it can be expanded and changed freely, it is not necessary to change or change the head part in accordance with the geology, hole diameter, etc. each time, and adapt to the geology. There is a remarkable effect such that the bulb portion d having the hole diameter a can be surely and easily formed.

Further, according to the present invention, the outer diameter dimension g of the spiral blade 5 attached to the auger head 3 and the upper casing 1
By forming the outer diameter dimension f of the spiral convex portion 2 attached to the shaft circumference to be substantially the same as the upper and lower diameters, the excavated soil rising due to the action with the conical inclined surface of the head in the underground pile hole is spread to the surrounding ground. It naturally consolidates to form a strong hole wall, does not disturb the ground underground, and has the effect of significantly reducing the amount of soil discharged, especially on the ground.

[Brief description of drawings]

FIG. 1 is a front view of a ground excavating device according to the present invention, where is a non-folded body view of a head portion, is an expanded body view,

[FIG. 2] (1), (2) and (3) are completed drawings of pile pile driving from a hole by an excavator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 2 Spiral convex part 3 Auger head 4 Cutting edge 5 Spiral wing piece 6 Hinge 7 Hydraulic jack 8 Mortar injection pipe 9 Mortar injection hole a Bulb hole diameter b Bulb hole c Mortar d Bulb portion P pile column

Claims (4)

[Claims] 1. A conical auger head, which is formed by attaching a cutting blade of an appropriate shape to the tip and integrally forming a spiral blade piece on the upper part of the cone-shaped auger head, is provided with a spiral projection above and below the shaft peripheral portion. An attempt is made to dig the ground by using a digging device A formed by connecting one part to a lower part of a casing integrally attached to the casing as a spindle so as to be capable of expanding and bending at a constant angle. An auger head part to be attached below the casing when the drilling device A is suspended by a pile driver on a predetermined ground, and thereafter, the power is moved to rotate the ground for excavation to reach a predetermined depth. The diameter of the bulb hole a is required to be expanded, and the casing is rotated and excavated by the bent expansion body of the auger head to excavate a large diameter bulb hole b at the bottom of the ground. To do. Thus, when the drilling of the bulb hole b having a predetermined diameter is completed in the ground, the bent body of the head is restored to its original state and the auger head is removed while the coagulating material c such as mortar is placed in the drill hole bulb hole b. A large diameter bulb portion b is formed in the ground by filling and forming a large diameter bulb portion d in the ground, and driving a pile pillar P into the excavation hole d using the bulb portion d as a root. A method for improving the foundation ground, which is characterized by trying to build a foundation layer that has a bearing capacity that is integrally held. 2. The method according to claim 1, wherein the auger head is formed below the casing by using a part of the auger head as a support shaft so that the head part can be expanded and bent at a constant angle. The ground is drilled by the hole drilling device A, and it is bent and expanded in a predetermined ground layer within the range of the bulb hole diameter a that requires the auger head, and the ground is rotated by the bent and expanded body. While excavating, at the same time, a condensing material c such as mortar is filled into the bulb hole b from the tip of the auger head, and the above-mentioned filled mortar is disturbed and kneaded by the bent body of the head portion to form a large mortar bulb portion in the ground. By forming d, and then returning the folding and expanding of the auger head portion to the original state, the auger head is pulled out to the ground together with the casing, and the pile pillar P is driven in the bore hole d to form the bulb. Bulb hole b with a large diameter in the ground with part d as the root A method for improving the foundation ground, which is characterized by attempting to build a ground layer integrally having 3. An auger head 3 having a generally conical shape as a whole, a tip blade 4 of an appropriate shape attached to a tip end thereof, and a spiral wing piece 5 integrally formed on the upper portion thereof. On the lower part of the casing 1 which is integrally provided with a spiral convex portion 2 on the peripheral part thereof, a hinge 6 or the like is used, and a part of the auger head 3 is used as a spindle and the other is movable such as a hydraulic jack 7. A drilling device for a foundation ground, characterized in that the whole auger head 3 is mounted by bending and expanding and contracting at a constant inclination angle with respect to a shaft of a casing so as to be able to be expanded and closed. 4. The drilling apparatus according to claim 2, wherein the vertical dimensional width g of the spiral wing piece 5 provided on the peripheral portion of the auger head 3 and the axial surface of the casing 1 connected to the upper portion of the head are provided. A drilling device for a foundation ground, characterized in that it is formed to have a diameter width f of the spiral convex portion 2 formed as a result of the above-mentioned diameter width f.