JP2006233749A - Construction method for root hardened part of pile hole, digging method for pile hole, construction device for root hardened part, and digging head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To construct a foundation pile having good quality in a short time by forming pile hole digging and root hardened layer/pile periphery fixing liquid layer efficiently. <P>SOLUTION: An axis part 22 and a bottom enlarged part 23 of a pile hole 21 are digged by a digging head 1 from the ground surface 20 (a), (b). Various digging liquids are supplied in the vertical direction 32 from a first discharge port 6 and in the horizontal direction 33 from a second discharge port 7 to supply digging liquids to parts in the vicinity of cutter tips 5a, 11a of digging cutting edges 5, 11. Next, root hardening liquid is injected in the vertical direction 32 from the first discharge port 6 and in the horizontal direction 33 from the second discharge port 7 (c). The root hardening liquid is spreaded over a wide scope in the horizontal direction by injecting the foot protection liquid radially in the horizontal direction. Then, a digging rod 14 is pulled up while injecting pile periphery fixing liquid through the first discharge port 6 and the second discharge port 7 (d). Most of required amount of foot protection liquid is supplied through the first discharge port 6 to supply to a part around a pile hole wall through the second discharge port 7. Next, an existing pile 26 forming an annular rib 27 is caused to sink in the pile hole 21 and fix it (e). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for constructing a root-solidified portion using a drilling head having different types of discharge ports, a first discharge port and a second discharge port, a method for drilling a pile hole, this building method, and a root-solidification used in the drilling method. This is related to the building construction equipment and drilling head.

  In the support pile, solidification material is injected into the lower end of the pile hole, cement milk having a higher solidification strength than the axial portion of the pile hole is injected, and the lower end of the foundation pile or reinforcing bar is buried in the rooting part. And built a foundation pile.

  At this time, the pile hole is excavated with the excavation blade of the excavation head, and the excavation head is attached through the hollow portion of the excavation rod as it is, and the pile hole is excavated to form a solidified portion with increased strength at the bottom of the pile hole. And improved the performance of foundation piles.

In the conventional technique, a valve is attached to the discharge port of the excavation head, and the opening and closing of the valve and the opening amount are operated from the ground to inject a predetermined amount of cement milk into the pile hole (Patent Document 1).
JP 2000-356086 A

  In the conventional technique, the opening amount of the valve attached to the excavation head is operated so that a predetermined amount of cement milk can be sprayed, so depending on the nature of the excavated soil in the pile hole, it is difficult to control the valve There was also a problem that occurred. In particular, when the excavation head is rotated or moved up and down to mix and mix the cement milk and the excavated soil, there is a risk of occurrence.

  In this case, in the construction method in which cement milk and excavated soil are sufficiently stirred and mixed to form a good-quality root consolidation part, there has been a strong demand for improving the quality of the root consolidation part.

  However, the present invention solves the above-mentioned problems because the solidified material such as cement milk whose pressure is adjusted on the ground is sprayed from the excavation head.

That is, according to the present invention, a solidified material is injected from a discharge port of the excavation head into a pile hole excavated by a excavation rod having an excavation head having a first discharge port and a second discharge port, and the root is formed in the pile hole. In the method for forming the solidified portion, the following procedure is taken.
(1) The solidified material is sprayed in the vertical direction from the first discharge port, and the solidified material is sprayed in the horizontal direction from the second discharge port simultaneously or before and after.
(2) Stir and mix the inside of the pile hole with the excavation head to form a solidified material layer,
(3) Thereafter, the excavation rod is pulled up to the ground.

In another aspect of the invention, the solidified material is injected into the pile hole excavated by the excavation rod having the excavation head having the first discharge port and the second discharge port from the discharge port of the excavation head. In the method of forming a root-solidified portion, a method for constructing a root-solidified portion of a pile hole characterized by taking the following procedure.
(1) The second discharge port disposed at a position close to the wall of the pile hole by injecting the solidified material from the first discharge port disposed at a position close to the bottom of the pile hole and simultaneously or before and after. The solidified material is sprayed from.
(2) With the excavation head, the inside of the pile hole is stirred and mixed to form a solidified material layer,
(3) Thereafter, the excavation rod is pulled up to the ground.

  In the method for constructing the root-solidifying portion, a flow path that reaches the discharge port of the excavation rod through the hollow portion of the excavation rod and the solidification material discharge device installed on the ground is formed, and the discharge amount or the discharge pressure is obtained by the solidification material discharge device. This is a method for constructing a root-solidifying portion, characterized in that a solidified material having a controlled viscosity is supplied to a first discharge port and a second discharge port, respectively. Further, the first discharge port is formed with a large diameter, or the solidification material can be injected in a large amount or at a low pressure, and the second discharge port is formed with a smaller diameter than the first discharge port, or the solidification material is formed in a small amount or a high pressure. This is a method for constructing a solidified portion, characterized in that it can be jetted with a hood.

Another invention is characterized in that a drilling rod having a drilling head having a first discharge port opened downward and a second discharge port opened in a radial direction is used, and the following procedure is taken. This is a method of drilling a pile hole.
(1) The drilling fluid is pressurized from the first discharge port and sprayed downward, and simultaneously or before and after, the pile hole is excavated while the drilling fluid is pressurized and sprayed laterally from the second discharge port.
(2) When a predetermined pile hole is excavated, the excavating rod is pulled up to the ground.

In another aspect of the present invention, there is provided a rooting portion building apparatus in which a hollow portion of a drilling head having a drilling blade and a solidification material transporting device are connected by a liquid feed path. It is.
(1) forming a first discharge port and a second discharge port in the excavation head portion;
(2) Open one side of the first liquid feed path having a large cross section to the first discharge port, and open one side of the second liquid feed path having a small cross section to the second discharge port,
(3) The other side of the both liquid supply paths was connected to the discharge port of the solidified material transport apparatus so that the pressure or flow rate could be adjusted.

Furthermore, another invention is an excavation head characterized by having the following configuration.
(1) A first discharge port and a second discharge port that are open to the outside air were formed in the excavation head.
(2) In the hollow portion of the excavation head, a first liquid feed path reaching the first discharge port is formed,
A second liquid feeding path reaching the second discharge port was formed.
(3) When the pile hole is excavated by the excavation head, the first discharge port is formed at a position close to the hole bottom of the pile hole, and the second discharge port is formed at a position close to the hole wall of the pile hole. An outlet was formed.

The large amount in the above means that the solidified material coming out from the first discharge port is a large amount at a relatively low pressure than the solidified material coming out from the second discharge port, and conversely, the small amount in the above means the solidified material coming out from the second discharge port. It means that the amount is relatively high and a small amount than the solidified material coming out of the first discharge port. For example,
・ From the first discharge port 0-30kg / cm ³
- from the second discharge port 100kg / ^cm 3 ~
It is conceivable to make the degree.

  Further, the vertical direction of the first discharge port in the above includes a deflection of about 45 degrees with respect to the vertically downward direction. The horizontal direction of the second discharge port includes a deflection of about 30 degrees above and 60 degrees below the horizontal direction.

  The excavation head to which the present invention is applied is suitable for a structure in which a swingable excavation arm is formed on the head body, but the structure such as a spiral excavation head is arbitrary, and the hollow excavation rod communicates with the hollow portion at the lower end. If the discharge port to be formed can be formed, all can be applied.

(1) In this invention, the solidification material is jetted in the vertical direction from the first discharge port of the excavation head, and the solidification material is jetted in the horizontal direction from the second discharge port, so that the amount of solidification necessary for the formation of the rooting portion is obtained. The material is supplied from the first discharge port to the center side of the pile-solidification part of the pile hole, and the solidification material is reliably supplied from the second discharge port to the hole wall side of the pile-hole consolidation part. There is an effect that a hole root consolidation part can be formed.

  In addition, since the solidification material is injected from the first discharge port close to the bottom of the pile hole and the solidification material is injected from the second discharge port close to the pile hole wall, the rooting liquid is sufficiently and reliably distributed to the pile hole wall. Since the soil mass can be finely pulverized and further stirred, there is an effect that a good-quality root hardening portion can be built in a short time.

(2) Further, in the case of (1), when the solidifying material is injected in a large amount or low pressure from the first discharge port and the solidifying material is injected in a small amount or high pressure from the second discharge port, further efficient solidifying material. It is possible to build a good-quality root hardening part in a short time.

  In particular, the high-pressure jet from the second discharge port at a position close to the pile hole wall can fill the solidified material all over the periphery of the root hardening portion in a short time. Therefore, it is possible to build a uniform and high-strength root hardening part. Further, in this case, when a drilling head having a swinging excavating arm is used, the earth lump crushed by the excavating arm or the like can be further finely pulverized by high-pressure jetting to build a good-quality root consolidation portion without uneven stirring.

(3) Moreover, if the drilling fluid is pressurized and ejected downward from the first discharge port, and the drilling fluid is pressurized and ejected radially from the second discharge port to excavate the pile hole, the drilling head can be used efficiently. There is an effect that can be excavated. In particular, even when a root is formed in a large diameter by injection from the second discharge port (for example, about twice the shaft diameter of the pile hole), the effect of accurately excavating the root is obtained. is there. Or a pile hole can be excavated, reducing the burden of an excavation head.

  In addition, when excavating a pile hole, it is possible to finely pulverize the clot by high pressure injection from the second discharge port, and to create a uniform pile hole (excavation hole) reliably up to the hole wall of the bottom of the pile hole it can.

(4) Further, since two liquid paths are formed in the excavation head and each is opened to the discharge port, there is an effect that liquids having different properties can be simultaneously supplied into the pile hole. Note that solidified materials having different concentrations and pressures can be considered as liquids having different properties.

(5) Further, since the solidified material is sprayed in the lateral direction from the second discharge port, even if the rooting portion is formed to have a large diameter, for example, about twice the diameter of the pile hole shaft portion, it is sufficiently rooted. There is an effect that a liquid can be filled to form a good-quality root hardening part.

(1) A hollow portion is formed in the head main body 2 having the excavating blades 5 and 5, and a large-diameter first conveying pipe 8 and a small-diameter second conveying pipe 9 are arranged in the hollow portion. The lower end of the first transport pipe opens to the first discharge port 6, and the lower portion of the second transport pipe branches into two and opens to the second discharge ports 7 and 7, respectively. Although it is possible to have at least one second discharge port 7 of the second transport pipe, it is desirable to form a plurality of second discharge ports 7.

  The excavation rod 14 is also formed with a hollow portion, and a large-diameter first transport pipe 8A and a small-diameter second transport pipe 9A are disposed in the hollow portion.

  The connecting portion 4 of the excavating head 1 is fitted and connected to the lower end connecting portion 15 of the excavating rod 14. At this time, the first transport pipe 8 and the second transport pipe 9 of the excavation head 1 and the first transport pipe 8A and the second transport pipe 9A of the excavation rod 14 are connected in the connecting portion 4 (FIG. 3A). ).

(2) In the above description, the first conveying pipe 8 having a large diameter and the second conveying pipe 9 having a small diameter are arranged along the second conveying pipe 9 (FIG. 3A). 9 can also be arranged (FIG. 3B). In this case, the branched second transport pipes 9, 9 pass under the first transport pipe 9, and the second transport pipes 9, 9 open to the first discharge ports 7, 7.

  In this case, the second transport pipe 9A is also disposed in the first transport pipe 8A even in the excavation rod 14 (FIG. 3B).

(3) The first transport pipe 8A is connected to the first supply port (large diameter) 18 of the cement milk transport device 17 through the first transport pipe 8B. 9 A of 2nd conveyance pipes are connected with the 2nd supply port (small diameter) 19 of the cement milk conveyance apparatus 17 via the 2nd conveyance pipe 9B (FIG. 1 (a)).

(4) By adjusting the first supply port 18 of the cement milk conveying device 17, a large amount of cement milk can be supplied into the pile hole from the first discharge port 6 at the lower end of the excavation head 1 at a relatively low pressure. Further, by adjusting the second supply port 19 of the cement milk conveying device 17, a relatively small amount of high-pressure cement milk can be supplied from the second discharge ports 7 and 7 on the side surface of the excavation head 1 into the pile hole. .

  Thereby, cement milk can be reliably filled also into the hole wall periphery of a pile hole root consolidation part, and a good quality root consolidation part can be formed.

(5) Further, when excavating pile holes, it is efficient to use the cement milk transport device 17 to transport various drilling liquids such as water from the supply ports 18 and 19 to the discharge ports 6 and 7 instead of cement milk. Drilling can also be realized.

(6) If such a drilling method using the first and second discharge ports is adopted, it is particularly effective in the case of a pile hole having a larger bottom diameter than the shaft part of the pile hole. For example, even if a pile hole is formed with a shaft diameter of 1000 mm of the pile hole and the root consolidation part is expanded to 2000 mm, a pile hole with a good dimensional accuracy (that is, a root consolidation part of a predetermined size) Homogeneous and elaborate). It can be built in the form of a cylinder with no soil mass in the root consolidation part, filled with more homogeneous soil cement, and with a well-prepared pile hole wall.

  Embodiments of the present invention will be described with reference to the drawings.

[1] Configuration of the excavation head 1

  The excavation head 1 of the present invention is configured by forming a horizontal shaft 3 on a side surface 2a of a hollow head body 2 and attaching excavation arms 10 and 10 to the horizontal shaft 3 so as to be swingable. The head main body 2 has a connection portion 4 that can be connected to a lower end connection portion 15 of a hollow excavation rod 14 having a passage at the upper end portion, and the passage of the excavation rod 14 and the hollow portion of the head main body 2 pass through the connection portion 4. And can communicate. Further, fixed excavation blades 5 and 5 are formed on the lower end portion of the head main body 2 downward. Excavation blades 11 and 11 are formed at the lower end of the excavation arm 10.

  The first discharge port 6 is formed between the fixed excavation blades 5 and 5 at the lower end of the head body 2, and the second discharge port is formed on the side surface 2 b that is substantially orthogonal to the horizontal axis 3 on the side surface of the head body 2. 7 is formed. Therefore, the second discharge port 7 is formed on a surface different from the rocking surface of the excavating arms 10 and 10.

  A large-diameter first transport pipe 8 inserted through the hollow portion of the excavation rod 2 reaches the inside of the head body 2 and opens to the first discharge port 6 at the lower end of the head body 2. Further, a second transport pipe 9 is inserted along the first transport pipe 8, and the second transport pipe 9 reaches the hollow portion of the head body 2 and branches in the hollow portion. , 7 is open. The two second discharge ports 7 and 7 are set at substantially the same height.

  On-off valves (not shown) are attached to the first outlet 6 and the second outlet 7, respectively. The excavation head 2 is configured as described above (FIG. 2).

[2] Drilling rod 14 and drilling device 30

(1) The excavation rod 14 has a lower end connection portion 15 that can be fitted to the connection portion 4 of the excavation head 2, and a hollow portion is formed over the entire length. In the hollow portion, a first transfer pipe 8A connected to the first transfer pipe 8 in the excavation head 2 and a second transfer pipe 9A connected to the second transfer pipe 9 in the excavation head 2 are respectively disposed (see FIG. 3 (a), FIG. 2). The first transfer pipe 8 and the first transfer pipe 8A have the same inner diameter, and the second transfer pipe 9 and the second transfer pipe 9A have the same inner diameter and are connected in the connecting portion 4 respectively. Further, a kneading drum 16 for leveling the pile hole wall is attached over the entire length of the excavation head 2 (FIGS. 1B to 1D).

(2) The excavation head 1 is connected to the tip 15 of the excavation rod 14 connected to the auger.

  Further, one end of the first transport pipe 8B is connected to the first supply port (large diameter) 18 of the cement milk transport device (solidified material transport device) 17 placed on the ground 20 and the second transport is transported to the second supply port (small diameter) 19. One end of each of the pipes 9B is connected. The other end of the first transport pipe 8B is connected to the first transport pipe 8A of the excavation rod 14, and the other end of the second transport pipe 9B is connected to the second transport pipe 9A of the excavation rod 14 (FIG. 1 (a)). .

  Accordingly, the first transport pipes 8, 8A and 8B formed with substantially the same inner diameter are integrally connected, and the second transport pipes 9, 9A and 9B formed with substantially the same inner diameter are integrally connected.

(3) The excavation apparatus 30 is comprised from the excavation rod 14 which connected the excavation head 1, the cement milk transport apparatus 17, and the conveyance pipes 8B and 9B which connected this (FIG. 1 (a)).

[3] Drilling method

(1) At a predetermined excavation position, the excavation rod 14 is rotated to excavate the shaft portion 22 of the pile hole 21 (FIG. 1A). At this time, if necessary, various drilling fluids such as water are supplied from the first discharge port 6 and / or the second discharge port 7. Accordingly, a relatively large amount of the drilling liquid is pressurized and injected to the center side of the pile hole 21 from the first discharge port 6 of the drilling head 1 vertically downward (in the direction of arrow 32) and fixed. Drilling fluid is supplied near the cutting edges of the drilling blades 5 and 5. Further, the drilling liquid is injected from the second discharge ports 7 and 7 of the excavation head 2 with a relatively small amount and a relatively large pressure in a horizontal radial direction (in the direction of arrows 33 and 33) to the outer peripheral side of the pile hole, Drilling fluid is supplied to the vicinity of the drilling blade 11 of the drilling arms 10 and 10.

  Since the drilling fluid is supplied in the vicinity of the cutting edges 5a and 11a of the respective drilling blades 5 and 11, efficient drilling can be realized even by supplying a small amount of drilling fluid. In particular, since the excavating blades 11 and 11 of the excavating arm 10 excavate so as to cut the pile hole wall 21a, the surface of the pile hole wall 21a is forcedly wetted and easily collapsed by the injection of the excavating liquid at high pressure. Therefore, excavation efficiency can be increased. Here, in order to prevent the pile hole shaft from collapsing, the drilling rod 14 is equipped with a kneading drum 16 for leveling the inner wall surface 21a of the pile hole or a stirring rod 16a for crushing and stirring the excavated soil. Is effective.

(2) Following the excavation of the shaft portion 22 of the predetermined pile hole 21, the excavation rod 14 (excavation head 2) is reversed to excavate the pile hole widening portion 23 (FIG. 1B). The excavation of the expanded bottom 23 is
a. Excavation with the diameter of the shaft portion 22 to the ground where a predetermined ground strength is confirmed, and then reversely expanding the excavation diameter to expand the hole wall so as to expand the hole wall. Form.
b. When the preset depth is reached, the excavation rod 14 is reversed, and the bottom 23 is formed by expanding the excavation from the depth downward and starting from the beginning. Continue expanding excavation to the ground where the predetermined ground strength is confirmed.
Any of these excavation methods can be adopted.

  However, the former a is suitable for the case where the ground strength is relatively low and it is easy to collapse and excavation is easy. The latter b is effective when the ground strength is relatively high and the excavation rod 14 needs to be strong against torsion, and excavation performance is not good.

  Further, when excavating the bottom-extended portion 23, similarly to the excavation of the shaft portion (1), if necessary, the drilling fluid is discharged vertically downward (in the direction indicated by 32) from the first discharge port 6, and the second The drilling fluid is discharged from the discharge ports 7 and 7 in a radial direction (in the direction of arrows 33 and 33) (see FIG. 1A).

(3) When excavation of the predetermined bottom-expanded portion 23 is completed, the root hardening liquid (rich cement powder) is jetted vertically downward (in the direction of arrow 32) from the first discharge port 7 of the excavation head 2 To do. At the same time, the root-setting liquid is sprayed horizontally (in the direction of arrows 33 and 33) from the second discharge ports 7 and 7 of the excavation head 2 (FIGS. 1C and 2). By spraying the root-setting liquid radially in the horizontal direction, the root-setting liquid spreads widely in the horizontal direction. Here, in order to develop a high bearing capacity on the ground, it is desirable to adjust the root hardening liquid so as to have a solidification strength higher than the strength of the supporting ground after stirring and mixing with the excavated soil.

  At this time, the excavation head 1 is rotated, and the excavation head 1 is raised and lowered at least once in the widened portion 23, and the cement milk and excavated soil are removed while leveling the pile hole wall 21 a with the kneading drum 16. It is desirable to stir and mix. Moreover, since the root hardening liquid from the second discharge ports 7 and 7 directly hits the pile hole wall 21a, which is easy to collapse, the pile hole wall 21a is strengthened, and the soil mass is finely crushed and stirred, so that it is homogeneous and high quality. A widened root 24 can be formed. Moreover, the expansion root part 24 can be formed in a shorter time by injection of cement milk from a plurality of locations.

  As described above, the construction of the enlarged root fixing portion 24 is completed.

(4) Subsequently, the digging rod 14 is pulled up toward the ground 20 while ejecting a pile fixing liquid (poor blended cement milk) from the first discharge port 6 of the digging head 1 with a relatively small pressure in large quantities. . At the same time, a small amount of pile periphery fixing liquid is ejected from the second discharge ports 7 and 7 with a relatively large pressure (FIG. 1 (d)). Pile circumference fixing liquid from the first discharge port 6 can supply most of the required amount, and the pile circumference fixing liquid from the second discharge ports 7 and 7 directly hits the pile hole fixing liquid directly near the pile hole The hole wall is also strengthened around the pile hole wall.

  At this time, if the excavation head 1 is rotated while pulling up the excavation rod 14, the pile peripheral shaft liquid 22 can be more uniformly filled with the pile circumference fixing liquid. As in the case of excavation, if the kneading drum 16 for leveling the pile hole wall and the stirring bar 16a for stirring the cement milk are formed, a more reliable pile hole 21 can be constructed.

(5) Subsequently, in the pile hole 21, the concrete ready-made pile 26 in which the annular ribs 27, 27 are formed at the lower end portion is sunk, and the annular rib 27 is located in the enlarged rooting portion 24. Fixing is performed (FIG. 1E). If the root hardening liquid of the enlarged root hardening part 24 solidifies, the root hardening part 24 more than the intensity | strength of a support ground can be formed.

(6) Moreover, the method of excavating a pile hole using the excavation head 1 which rocks the excavation arms 10 and 10 attached to the head main body 2 like an Example makes the shape of the excavation head 1 comparatively small. Nevertheless, compared with the conventional method, it was possible to accurately excavate a large-diameter pile hole and a larger-diameter bottom expanded portion, thereby greatly improving the efficiency of excavating the pile hole. However, there have been excavation heads 1 using the excavation arms 10 and 10 such as a ground where the excavation arms 10 and 10 have a large burden and the excavation time is long, and a ground that cannot sufficiently pulverize a clot. Even in this case, if the first and second discharge ports 7 and 8 are used in combination, the burden on the excavating arms 10 and 10 is reduced, and the clot is pulverized in a short time, thereby expanding the large-diameter bottom portion. Can be drilled accurately and efficiently.

[3] Other embodiments

  In the embodiment, the second discharge port 7 is formed on the side surface of the excavation head 1, but it can also be formed on the excavation arms 10 and 10. In this case, the excavating arm 10 is formed in a hollow shape, and the second transport pipes 9 and 9 are passed to the second discharge port 7 (not shown).

  Moreover, in the said Example, although the drilling liquid was inject | poured at the time of excavation, injection | pouring of a drilling liquid can also be abbreviate | omitted.

  In the above-described embodiment, “the fixed excavation blade 5 and the excavation blade 11 of the excavation arms 10 and 10 are not used” or “the excavation head in which one or both of the fixed excavation blade 5 and the excavation blade 11 are omitted” is used. The pile hole can also be excavated by only the pressurized ejection of the drilling fluid from the first discharge port 6 and the second discharge port 7 (not shown).

  Moreover, in the said Example, although the root consolidation part was used as the enlarged root consolidation part 24, a root consolidation part can also be excavated by the same diameter as the pile hole axial part 22 (not shown).

Moreover, in the said Example, the 1st discharge port 6 is filled with the pile hole filling via the 1st supply port 18, the 1st conveyance pipe 8, 8A, 8B, and the 2nd discharge port 7 is filled with it. Since the pile hole filling can be filled through the second supply port 19 and the second transport pipes 9, 9A, 9B, different types of pile hole filling can be supplied to the discharge ports 6, 7, respectively. For example, cement milk mixed with various admixtures for reinforcing the pile hole wall 21a can be discharged from the second discharge port 7 (not shown).
In addition, when discharging the same type of pile hole filler, it is possible to adjust the opening and closing of the valves of the discharge ports 6 and 7 in the vertical direction (or the pile hole bottom) by adjusting the opening and closing of the valves of the discharge ports 6 and 7 as in the past. A predetermined amount of pile hole filling material (not shown) in the lateral direction (or the side close to the pile hole wall).

  Moreover, although the said 2nd discharge port 7 was provided in the horizontal direction, it can also be installed slightly diagonally upward or diagonally downward, or can be attached so that an angle can be changed (not shown).

  Moreover, in the said Example, although the excavation head 2 was attached and the excavation rod 14 was comprised, the excavation head 2 can also be integrally formed in the lower end part of the excavation rod 14 (not shown).

(A)-(e) is the schematic longitudinal cross-sectional view explaining the construction method of the Example of this invention. It is an enlarged front view of the excavation head used for the Example of this invention. (A) (b) is a conceptual diagram showing arrangement | positioning of the pipe in a head similarly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Excavation head 2 Head main body 3 Horizontal axis 4 Head main body connection part 5 Head main body fixed excavation blade 6 Head main body first discharge port 7 Head main body second discharge port 8 Head main body first conveyance pipe 9 Head main body Second conveying pipe 10 Excavating arm 11 Excavating arm excavating blade 14 Excavating rod 15 Lower end coupling 16 of excavating rod Kneading drum 16a Stirring bar 17 Cement milk transporting device 18 First supply port 19 of cement milk transporting device 19 Second supply port 20 Ground (ground)
DESCRIPTION OF SYMBOLS 21 Pile hole 22 Shaft part 23 of pile hole Expanded bottom part 24 of pile hole Expanded solidification part 26 Ready-made pile 27 Ring-shaped rib 30 of ready-made pile Excavator

Claims (7)

A solidified material is injected into the pile hole excavated by the excavation rod having the excavation head having the first discharge port and the second discharge port from the respective discharge ports of the excavation head to form a rooted portion in the pile hole. In the method, the construction method of the solidified part of a pile hole characterized by taking the following procedures.
(1) The solidified material is sprayed in the vertical direction from the first discharge port, and the solidified material is sprayed in the horizontal direction from the second discharge port simultaneously or before and after.
(2) Stir and mix the inside of the pile hole with the excavation head to form a solidified material layer,
(3) Thereafter, the excavation rod is pulled up to the ground. A solidified material is injected into the pile hole excavated by the excavation rod having the excavation head having the first discharge port and the second discharge port from the respective discharge ports of the excavation head to form a rooted portion in the pile hole. In the method, the construction method of the solidified part of a pile hole characterized by taking the following procedures.
(1) The second discharge port disposed at a position close to the wall of the pile hole by injecting the solidified material from the first discharge port disposed at a position close to the bottom of the pile hole and simultaneously or before and after. The solidified material is sprayed from.
(2) With the excavation head, the inside of the pile hole is stirred and mixed to form a solidified material layer,
(3) Thereafter, the excavation rod is pulled up to the ground. Form a flow path to the discharge port of the excavation rod through the solidified material discharge device installed on the ground and the hollow part of the excavation rod,
3. The construction of a rooting portion according to claim 1 or 2, wherein the solidification material with the discharge amount or the discharge pressure adjusted is supplied to the first discharge port and the second discharge port by the solidification material discharge device, respectively. Method. The first discharge port is formed with a large diameter, or the solidification material can be injected in a large amount or at a low pressure, and the second discharge port is formed in a smaller diameter than the first discharge port, or the solidification material is injected with a small amount or a high pressure. The method for constructing a rooted portion according to any one of claims 1 to 3, characterized in that it is possible. A method for excavating a pile hole using a drilling rod having a drilling head having a first discharge port opened downward and a second discharge port opened in a radial direction, and taking the following procedure.
(1) The drilling fluid is pressurized from the first discharge port and sprayed downward, and simultaneously or before and after, the pile hole is excavated while the drilling fluid is pressurized and sprayed laterally from the second discharge port.
(2) When a predetermined pile hole is excavated, the excavating rod is pulled up to the ground. A rooting portion building device having the following characteristics in a rooting portion building device in which a hollow portion of a drilling head having a drilling blade and a solidifying material transporting device are connected by a liquid feed path.
(1) forming a first discharge port and a second discharge port in the excavation head portion;
(2) Open one side of the first liquid feed path having a large cross section to the first discharge port, and open one side of the second liquid feed path having a small cross section to the second discharge port,
(3) The other side of the both liquid supply paths was connected to the discharge port of the solidified material transport apparatus so that the pressure or flow rate could be adjusted. An excavation head having the following configuration.
(1) A first discharge port and a second discharge port that are open to the outside air were formed in the excavation head.
(2) In the hollow portion of the excavation head, a first liquid feed path reaching the first discharge port is formed,
A second liquid feeding path reaching the second discharge port was formed.
(3) When the pile hole is excavated by the excavation head, the first discharge port is formed at a position close to the hole bottom of the pile hole, and the second discharge port is formed at a position close to the hole wall of the pile hole. An outlet was formed.

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