JPH05321253A - Boring device - Google Patents

Abstract

PURPOSE:To provide a hole having a sectional form suitable for the object of boring. CONSTITUTION:A casing 20 is fitted on an auger screw 5 which rotates round the axis and bores the ground G. At the tip of the easing 20 a cutter 30 is mounted, and its ridge 32a as a cutting edge is protruded from the tip of the casing 20 in the axial and radial directions. The gap O between a sheet pile PB, fitted at, the periphery of the casing 20, and the casing 20 is blocked by this cutter 30, and its tip is protruded in the axial direction from the sheet pile PB. Preceding to the casing 20, the ground G is cut and collapsed by the cutter 30, and a hole H bored by the auger screw 5 is widened alongside the section of the sheet pile PB so that the fit-in resistance to it is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a punching device in which a casing is fitted around the outer circumference of a punching member such as an earth auger.

[0002]

2. Description of the Related Art A conventional punching device of this type has been shown in FIG.
The ones shown in are known. The punching device 1 is used for press-fitting the sheet pile PB into the ground G, and is vertically moved up and down by a driving means (not shown) such as a hydraulic motor guided by a leader 3 standing on the front surface of the working machine body 2. Drive unit 4, an auger screw 5 hung from the drive unit 4 and driven to rotate about an axis by a drive means (not shown) such as a hydraulic motor, and fitted coaxially to the outer peripheral side of the auger screw 5. And a casing 6 whose upper end is fixed to the drive unit 4. And casing 6
As shown in FIG. 15, a sheet pile PB having a substantially U-shaped cross section is attached to the casing 6 along the outer periphery of the casing 6. In order to press fit the sheet pile PB using the punching device 1, the drive unit 4 is lowered while rotating the auger screw 5, and the ground G is punched at the tip of the auger screw 5 as shown in FIG. At the same time, the casing 6 is pressed into the hole H formed by the auger screw 5 together with the sheet pile PB.
Accordingly, the sheet pile PB is guided by the casing 6 and is press-fitted straight into the ground G without bending toward the center of the hole H. After the perforation up to the desired depth is completed, the auger screw 5 and the casing 6 are removed leaving the sheet pile PB.
According to the above, the casing 6 is formed after the ground G is drilled in advance.
Further, since the sheet pile PB is press-fitted, the press-fitting resistance is smaller than that when the sheet pile PB is driven alone, and the sheet pile PB can be press-fitted efficiently.

Incidentally, the auger screw 5 and the casing 6
The use of the punching device that also uses is not limited to the press-fitting of the sheet pile PB. For example, in the construction of the foundation pile, as shown in FIG. 17, the casing 6 is press-fitted to protect the hole wall while piercing the ground G with the auger screw 5, and after completion of the piercing, only the auger screw 5 is removed to remove the inside of the casing 6. There is a case where H steel 7 is built in and then, while the casing 6 is removed, a solidified material such as cement is injected into the hole to form a foundation pile.

[0004]

By the way, the above-described conventional perforating apparatus 1 has the following problems because the cross-sectional shape of the hole H to be perforated by the auger screw 5 is limited to a circular shape. When used for press-fitting sheet pile PB, sheet pile P
Since the sectional shape of B and the sectional shape of the casing 6 do not match, even if the sheet pile PB is brought into close contact with the outer periphery of the casing 6 as shown in FIG. 15, a gap O is formed between the corner E of the sheet pile PB and the casing 6. Occurs. The ground G located on the gap O is not excavated by the auger screw 5 and is collapsed by the tip of the corner E of the sheet pile PB as shown in FIG. 16, so that the press-fit resistance of the sheet pile PB is increased and the ground G is hard. In some cases, it may take a long time to break it down. In addition, sheet pile P
The earth and sand ES destroyed by B may enter the gap O, and the press-fit resistance of the sheet pile PB may increase.

When used for the construction of foundation piles, the diameter of the hole H must be larger than the diagonal dimension hmax of the H steel 7, so that the auger screw 5 and the auger screw 5 that are considerably larger than the width h of the H steel 7 and Since the casing 6 must be prepared, the device becomes large. Further, if the diameter of the auger screw 5 is increased, the excavation volume is increased accordingly and the amount of soil discharged is increased, so that it takes time and labor to process it. Furthermore, since a large gap remains between the H steel 7 and the hole wall, the amount of solidified material required to harden the periphery of the H steel 7 also increases. Incidentally, the minimum cross-sectional area A of the hole H with respect to the width h of the H steel 7 is A = (√2h) ² × π / 4 = 1.57h ² .

The above-described punching device 1 may also be used when forming a horizontally long hole H _L in the ground G as shown in FIG. 18, but in such a case, a single cross-section is circular in cross section. Since only the holes H of
_n-1 and allowed to partially overlap to form the following holes H _n, must still form a next hole H _{n + 1} with the hole H _n and is partially overlapped. For this reason, the number of drilling required until the hole _HL reaches the predetermined length is remarkably increased and the construction efficiency is lowered. Moreover, since the surplus soil G _R remains the border of the hole H between as shown in FIG hatched portion, it is necessary to work to remove it after the excavation.

An object of the present invention is to provide a punching device capable of forming a hole having a cross-sectional shape according to the purpose of punching.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described with reference to FIG. 1 showing an embodiment. In the present invention, a piercing member 5 for piercing the ground by rotating around an axis, and an outer periphery of the piercing member 5 are fitted. The present invention is applied to a perforating apparatus 10 provided with a hollow casing 20 that is mounted and is press-fitted into the ground together with the perforating member 5.
The above-described object is achieved by mounting the cutter 30 having the cutting edge 32a on the casing 20 so that the cutting edge 32a projects in the axial direction and the radial direction from the tip of the casing 20.

In the punching device 10 of claim 2, the cutter 30 is used.
In order to improve the dischargeability of the earth and sand ES that is collapsed by the inner side surface 32b of the side surface of the cutter 30 that protrudes from the tip of the casing 20 and faces the center side in the radial direction of the casing 20.
Was moved closer to the radial center of the casing 20 as the tip of the cutter 32 was retracted toward the tip of the casing 20.
The punching device 10 according to claim 3 is suitable for press-fitting a sheet pile PB, in which a cutter 30 closes a gap O formed between the sheet pile PB mounted on the outer periphery of the casing 20 and the casing 20, and a cutting edge thereof. It is characterized in that the ridge 32a is provided so as to protrude from the gap O over the tip of the sheet pile PB in the axial direction of the casing 20. The punching device according to claim 4 is suitable for construction of foundation piles, and as shown in FIG. 9, a cutter 60 is provided so as to draw a rectangular outer peripheral contour S around the casing 60. To do.

[0010]

In the punching device 10 of the first aspect, the casing 20 is provided.
At the time of press-fitting, the cutting edge ridge 32a of the cutter 30 is cut into the hole wall of the hole H punched by the punching member 5 and a part of the hole wall is cut away, whereby the hole wall has a sectional shape of the cutter 30. Can be expanded according to. In the punching device 10 according to claim 2, the cutter 30 is provided.
The earth and sand destroyed by is guided to the inside of the casing 20 along the inner surface 32b of the cutter 30. Drilling device 1 according to claim 3.
At 0, the punching member 5 is provided by the cutter 30 provided so as to close the gap O between the sheet pile PB and the casing 20.
The hole H having a circular cross section formed by is expanded along the cross sectional shape of the sheet pile PB. In the punching device 40 according to the fourth aspect, the hole H having a circular cross section formed by the punching member 5 is expanded into a rectangular cross section.

Incidentally, in the section of means and actions for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for the purpose of making the present invention easy to understand. It is not limited to.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. The same components as those of the conventional example described above are designated by the same reference numerals, and the description thereof is partially omitted.

First Embodiment As shown in FIGS. 1 and 2, the punching device 10 of the present embodiment.
Is used when press-fitting the sheet pile PB into the ground G, and the auger screw 5 that rotates around the axis to punch the ground G, and the auger screw 5 that is coaxially fitted to the outer periphery of the auger screw 5 is used. A hollow casing 20 that is press-fitted into the ground is also provided. As shown in FIG. 3, in the auger screw 5, a plurality of spiral guide plates 5b are arranged on the outer periphery of a core 5a extending along the axis, and a bit 5c for breaking the ground is provided at the tips of the core 5a and the guide plate 5b. It is attached and is hung from a drive unit 4 that moves up and down along a leader 3 of the working machine, and is driven around an axis by a hydraulic motor in the drive unit 4 (see FIG. 1).
4). As shown in FIG. 4, the casing 20 has a flange 21 at its upper end, and by fixing this flange 21 to the lower end of the drive unit 4, the casing 20 can be moved up and down in synchronization with the auger screw 5.

As shown in FIGS. 4 to 6, the casing 20
A sheet pile engaging portion 22 is provided on the outer peripheral portion of the tip end of the. The sheet pile engaging portion 22 has a pair of push plates 22a protruding from the outer peripheral surface 20a of the casing 20, and a pair of insertion shafts 22b attached to the tip of the push plate 22a and extending in the axial direction of the casing 20. By inserting the insertion shaft 22b into the gap between the beam B of the sheet pile PB arranged along the outer periphery of the sheet 20 and the corner portion E of the sheet pile 20 and engaging the lower end of the push plate 22a with the beam B, With the press-fitting operation into the ground, the push plate 22a presses the beam B of the sheet pile PB so that the entire sheet pile PB can be pulled into the ground.

As shown in FIGS. 4, 5, and 7, a pair of cutters 30 is attached to the tip of the casing 20. These cutters 30 are provided on the outer peripheral surface 2 of the casing 20.
It has an attachment part 31 welded to the casing 0a and an excavation part 32 protruding from the tip of the casing 20. The mounting portion 31 is
The protrusion amount in the radial direction from the outer peripheral surface 20 a of the casing has a substantially triangular pyramid shape that increases toward the tip of the casing 20. The excavation portion 32 has a substantially triangular pyramid shape that protrudes sharply in the axial direction of the casing 20, and the amount of protrusion in the radial direction from the casing outer peripheral surface 20a is constant. Then, on both sides of the excavated portion 32, cutting edge ridges 32a extending from the tip of the excavated portion 32 toward the base end are formed.

As shown in FIGS. 1 and 2, the cutting edge 32
The inner side surface 32b connected to a has a concave curved surface shape that approaches the radial center of the casing 20 from the tip of the cutter 30 toward the tip of the casing 20, and the radius of curvature R thereof impairs the strength of the excavated portion 32. It is set large enough so that there is no The inner side surface 32b has a radius of curvature R of zero,
That is, it may be formed on an inclined surface having a constant gradient.

Each cutter 30 has a casing 20.
Sheet pile PB and casing 20 that engage with the sheet pile engaging portion 22 of
The mounting position, the cross-sectional shape, and the size of the excavating portion 32 are determined so as to close the gap O formed therebetween and to project the tip of the excavation portion 32 from the gap O over the tip of the sheet pile PB to the tip in the axial direction of the casing 20. Has been.

Using the punching device 10 of this embodiment, the ground G
In order to press-fit the sheet pile PB into the casing 20, the sheet pile PB is arranged on the outer periphery of the casing 20 and the tip portion thereof is engaged with the sheet pile engaging portion 22, and then the auger screw 5 is used to ground the ground sheet G as shown in FIG.
While perforating the casing 20, the casing 20 is press-fitted into the hole H to be perforated by the auger screw 5. As a result, the sheet pile PB is pressed by the push plate 22a of the sheet pile engaging portion 22 of the casing 20 and is pressed into the ground G together with the casing 20. After the perforation is completed to the desired depth, the auger screw 5 and the casing 20 are pulled out to release the engagement between the sheet pile PB and the sheet pile engaging portion 22 of the casing 20 to remove the sheet pile PB.
Leaving only in hole H.

In the case of the above procedure, the cutting edge ridge 32a of the cutter 30 breaks down the ground G prior to the press-fitting of the casing 20, so that the hole H of circular cross section formed by the auger screw 5 forms the sheet pile PB and the casing 20. It is widened in the radial direction along the shape of the gap O between and. Therefore, the amount by which the ground G is pushed down at the tip of the sheet pile PB is extremely small. Moreover, the resistance when the cutter 30 cuts the ground G is much smaller than the resistance when the sheet pile PB having no cutting edge ridges breaks the ground G. Therefore, the press-fitting resistance of the sheet pile PB is remarkably reduced as compared with the conventional one, and the sheet pile P is easily laid even on the hard ground G.
The work can be completed in a short time by press-fitting B. In this embodiment, since the gap O is closed by the cutter 30,
There is no possibility that the earth and sand ES cut by the cutter 30 will enter the gap O and increase the press-fitting resistance. The earth and sand ES are smoothly guided to the inside of the casing 20 along the inner surface 32b of the cutter 30 and rapidly discharged to the ground by the auger screw 5, so that the earth and sand ES can be discharged well.

-Second Embodiment- Next, an embodiment in which the present invention is applied to a boring device for constructing foundation piles will be described. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. As shown in FIGS. 8 and 9, the punching device 40 of the present embodiment is different from the first embodiment in that the sheet pile engaging portion is removed from the outer periphery of the casing 50 fitted to the outer peripheral side of the auger screw 5. Also, at the tip of the casing 50, a total of four cutters 60 each having a pair of cutting edge ridges 60a and each having a substantially triangular pyramid shape are attached at positions that divide the casing 50 into four equal parts in the circumferential direction. is there. The cutters 60 have a cross-sectional shape and dimensions so as to draw a square outer peripheral contour S around the casing 50 in a plan view (FIG. 9) from the axial direction of the casing 50. As in the first embodiment, the inner side surface 60b of the cutter 60 facing the casing center side is closer to the radial center of the casing 50 as the tip end of the cutter 60 is retracted toward the casing 50. ..

[0021] In this embodiment, by the casing 50 is pressed into the ground following the perforation by the auger screw 5, as shown in FIG. 10, the hole H _O of a circular cross section to be drilled by auger screw 5 is The cross-sectional shape of the hole H _S obtained by enlarging according to the outer peripheral contour S of the cutter 60 is square. Therefore, the H steel 7 built into the hole H _S
It is possible to use the auger screw 5 and the casing 50 having a diameter smaller than the diagonal dimension hmax of (3), and it is possible to downsize the device. Further, since the cross-sectional area of the hole H _S is smaller than that of the conventional one, the amount of soil discharged is reduced, and the amount of the solidified material injected into the hole H _S is also small. By the way, the minimum cross-sectional area of the hole H _S is h ^2, which is 36% compared to the conventional minimum cross-sectional area.
It is reduced to some extent.

In this embodiment, since the hole H _S having a square cross section can be formed, even when the horizontally long hole H _L is formed as shown in FIG. 11, the plurality of holes H _S are arranged so that their boundaries are in contact with each other. It only needs to be repeatedly formed, the number of drilling is significantly reduced, and it is not necessary to remove the residual soil at the boundary between the holes H _S after the drilling, and the working efficiency is significantly improved. further,
Since the hole wall of each hole H _S is flat, the hole wall can be finished better than in the case where a hole having a circular cross section is formed and then cut into a flat shape. In addition, when forming the horizontally long hole H _L in this way, as shown in FIG. 12 and FIG.
By arranging two or more 0's in series and making holes at the same time,
The construction efficiency can be further improved.

The cutters 30 and 60 described in the above embodiments
The arrangement and shape of the cutter are merely examples, and the shape and arrangement of the cutter in the present invention may be variously changed according to the purpose of punching. For example, in the first embodiment, the cross sectional shape and the arrangement of the cutter 30 are appropriately changed according to the change in the cross sectional shape of the sheet pile PB. Further, in the second embodiment, it is possible to obtain an arbitrary polygonal cross section according to the arrangement and size of the cutter 60, such as forming three or five or more cutters 60 to form holes having a triangular or pentagonal cross section.

[0024]

As described above in detail, according to the present invention, since the hole wall of the hole formed by the perforating member is widened according to the sectional shape of the cutter, the arrangement and sectional shape of the cutter,
By appropriately selecting the size, an excellent effect that a hole having a sectional shape suitable for the purpose of drilling can be easily formed is obtained. In the punching device of the second aspect, since the earth and sand broken by the cutter is smoothly introduced into the casing, the earth and sand discharging property is improved. In the punching device according to the third aspect, since the hole wall formed by the punching member is expanded along the cross-sectional shape of the sheet pile by the cutter, the press-fitting resistance of the sheet pile is reduced and the efficiency of the sheet-sheet press-fitting work is improved. In the punching device according to claim 4, since the hole wall formed by the punching member is expanded to have a rectangular cross section, the diameter of the punching member and the casing can be reduced when constructing the foundation pile to achieve downsizing of the device. It is possible to reduce the amount of soil discharged and the amount of coagulant injected into the hole after drilling.

[Brief description of drawings]

FIG. 1 is a diagram showing a state in which a sheet pile is press-fitted while perforating the ground by the perforating apparatus according to the first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is an enlarged view showing a tip portion of an auger screw of the punching device of FIG.

4 is a side view of a casing of the punching device of FIG. 1. FIG.

5 is a diagram showing a state in which the front end portion of the casing of FIG. 4 is viewed from the V direction in FIG.

6 is a diagram showing a sheet pile engaging portion of the casing of FIG.
6A is a sectional view taken along line VI-VI in FIG. 5, and FIG.
Sectional view taken along line VI _B -VI _B of (A)

FIG. 7 is a diagram showing a state in which the casing distal end portion of FIG. 5 is viewed from the VII direction in FIG.

FIG. 8 is a perspective view showing a casing tip portion of a punching device according to a second embodiment of the present invention.

9 is a diagram showing a state of the casing of FIG. 8 viewed from the IX direction in FIG.

10 is a view showing a state in which H steel is built in the holes formed by the punching device of FIG.

11 is a view showing a state in which a horizontally long hole is formed by the punching device of FIG.

FIG. 12 is a view showing a modification of the punching device of FIG.

FIG. 13 is a diagram showing a state in which the punching device of FIG. 12 is viewed from the XIII direction in FIG.

FIG. 14 is a view showing a state in which a punching device is attached to a working machine to perform a punching operation.

15 is a sectional view taken along line XVI-XVI in FIG.

FIG. 16 is a view showing a state in which a sheet pile is press-fitted while punching the ground using a conventional punching device.

FIG. 17 is a view showing a state where H steel is built in a hole formed by a conventional punching device.

FIG. 18 is a view showing a state in which a horizontally long hole is formed by a conventional punching device.

[Explanation of symbols]

 5 Auger screw 10,40 Drilling device 20,50 Casing 30,60 Cutter 32a, 60a Cutting edge 32b, 60b Inner surface of cutter G Ground H Hole O Gap between sheet pile and auger screw PB Sheet pile S Outer contour of cutter

Claims (4)

[Claims] 1. A piercing device comprising: a piercing member that rotates around an axis to pierce the ground; and a hollow casing that is fitted to the outer periphery of the piercing member and is press-fitted into the ground together with the piercing member. A punching device, wherein a cutter having a cutting edge is attached to the casing so that the cutting edge projects from an end of the casing in an axial direction and a radial direction. 2. The inner side surface of the cutter, which protrudes from the tip of the casing and faces the radial center side of the casing, recedes from the tip of the cutter to the tip of the casing in the radial direction of the casing. The punching device according to claim 1, wherein the punching device is close to the center side. 3. The cutter closes a gap formed between a casing attached to the outer periphery of the casing and the casing, and a cutting edge of the cutter extends from the gap beyond the tip of the sheet pile. The punching device according to claim 1 or 2, wherein the punching device is provided so as to project in the axial direction. 4. The punching device according to claim 1, wherein the cutter is provided so as to draw a rectangular outer peripheral contour around the casing.