JP2019178551A - Construction method of pile-like reinforcement body and filling head - Google Patents

Abstract

To provide a construction method of a pile-like reinforcement body and a filling head allowing a construction period to be shorter in an environment where an additional operation to attach a filling head is required.SOLUTION: A construction method of a pile-like reinforcement body includes: a connection process (step S1) connecting a pile head 1a of an expandable-type steel pipe pile 1 to a filling head 2 to each other; a press-inserting process (step S2) press-inserting the expandable-type steel pipe pile 1 into the ground 6 in a situation where the pile head 1a and the filling head 2 are connected to each other after the connection process (step S1); and a filling process (step S3) filling press-fluid inside of the expandable-type steel pipe pile 1 through the filling head 2 after the press-inserting process (step S2).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a pile-shaped reinforcing body creation method for press-fitting an expanded steel pipe pile into the ground, and an injection head for injecting a pressure fluid into the expanded steel pipe pile.

  As this kind of pile-shaped reinforcement production method and injection head which were used conventionally, the structure described in the following patent documents 1, 2 grade | etc., Can be mentioned, for example. In Patent Document 1, after a press-fitting jig having a tapered shape is press-fitted into the ground, the press-fitting jig is removed from the ground, thereby forming a recess having an inner peripheral wall made of compacted or compacted soil in the ground. The pile-shaped reinforcement production method which press-fits an expansion type steel pipe pile in the ground so that a pile head may be located in the recessed part is described. The recess secures a space for attaching the injection head to the pile head. Patent Document 2 describes an injection head having a handle attached so as to be easily attached to a pile head in the ground.

JP 2017-110426 A JP 2017-110428 A

  In said patent document 1, it has proposed forming a recessed part in the ground with a press-fitting jig. If it is a general ground, a recessed part can be formed in the ground by such a method, and an injection | pouring head can be attached to the pile head in a recessed part. However, in the case of soft ground, or when the head portion of the reinforcing material is remarkably deep, work for removing the ground through heavy machinery occurs, and the construction period becomes longer. Even if the concave portion is formed in the ground by the press-fitting jig, the concave portion may collapse and the pile head may be buried in the soil. When the pile head is buried in the soil, it is necessary to dig up the pile head and clean the pile head. In addition, in the case of ground with a high groundwater surface, the pile head may be located below the water surface and the position of the pile head may be difficult to confirm even if the recess does not collapse. That is, only the conventional method as described above may cause additional work for attaching the injection head, and the construction period may be long.

  The present invention has been made to solve the above-described problems, and its object is to provide a pile-shaped reinforcing body creation method and an injection head that can shorten the construction period in an environment where additional work is required to attach the injection head. Is to provide.

  The pile-shaped reinforcement body creation method which concerns on 1 aspect of this invention is the state in which the pile head and the injection | pouring head were mutually connected after the connection process which connects the pile head and injection | pouring head of an expansion type steel pipe pile mutually. The press-in process of press-fitting the expandable steel pipe pile into the ground, the injection process of injecting the pressure fluid into the expandable steel pipe pile through the injection head after the press-in process, and the process of removing the injection head from the pile head.

  An injection head according to an aspect of the present invention is an injection head that is connected to a pile head of an expandable steel pipe pile and injects a pressure fluid into the expandable steel pipe pile, and includes a head main body and a lower surface of the head main body. It is provided in the head body so as to open, and is located in the upper surface when viewing the upper surface of the head body along the extending direction of the pile head insertion hole and the pile head insertion hole for inserting the pile head And a hose connection joint extended from the upper surface.

  An injection head according to an aspect of the present invention is an injection head that is connected to a pile head of an expandable steel pipe pile and injects a pressure fluid into the expandable steel pipe pile, and has a stepped portion inside. And an inner plug that is inserted into the inside of the head main body through an opening provided on the upper surface of the head main body, and the upper lid is connected to the upper surface of the head main body, whereby the upper lid and the stepped portion The inner plug is held between the two.

  Furthermore, an injection head according to an aspect of the present invention is an injection head that is connected to a pile head of an expandable steel pipe pile and injects a pressure fluid into the expandable steel pipe pile, the head main body, It is provided in the head body so as to open on the lower surface, and is engaged with a pile head insertion hole for inserting the pile head and a pile head inserted into the pile head insertion hole, A holding mechanism for holding the pile head.

  According to the pile-shaped reinforcing body creation method according to one aspect of the present invention, the pile head and the injection head are connected to each other after the connection step of connecting the pile head and the injection head of the expandable steel pipe pile to each other. It includes a press-fitting process for press-fitting the expanded steel pipe pile into the ground in a state where it is inserted, and an injection process for injecting a pressure fluid into the expanded steel pipe pile through the injection head after the press-fitting process. The construction period can be shortened in an environment where work occurs.

  According to the injection head according to one aspect of the present invention, the hose connection joint extends from the upper surface of the head body so as to be positioned in the upper surface when the upper surface of the head body is viewed along the extending direction of the pile head insertion hole. As a result, it is possible to reduce the risk of damage to the hose connection joint when the injection head is pressed into the ground together with the expanded steel pipe pile, and the construction period is shortened in an environment where additional work is required to install the injection head more securely. it can.

  Further, according to the injection head according to one aspect of the present invention, the inner plug is inserted into the inside of the head body from the opening provided on the upper surface of the head body so as to freely advance and retract. Since the inner plug is held between the inner plug and the head main body, the inner plug and the head main body can be less likely to be damaged due to the pressure at the time of press-fitting as compared with the mode in which the inner plug is screwed into the head main body. The construction period can be shortened in an environment where additional work is required to reliably attach the injection head.

  Furthermore, according to the injection head according to one aspect of the present invention, since the holding mechanism holds the pile head in the pile head insertion hole, the expansion type steel pipe pile is mounted after the injection head is attached to the pile head of the expansion type steel pipe pile. It can be prevented from falling off, and the construction period can be shortened in an environment where additional work is required to attach the injection head more reliably.

It is explanatory drawing which shows the pile-shaped reinforcement production method by embodiment of this invention. FIG. 2 is a cross-sectional view of the injection head of FIG. FIG. 3 is a plan view showing the injection head of FIG. 2. FIG. 3 is a bottom view of the injection head of FIG. 2. It is a front view which shows the attachment of FIG. It is a bottom view which shows the attachment of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In addition, this invention is not limited to each embodiment, A component can be deform | transformed and embodied in the range which does not deviate from the summary. Moreover, you may delete some components from all the components shown by embodiment.

  FIG. 1 is an explanatory diagram showing a pile-shaped reinforcing body creation method according to an embodiment of the present invention. The pile-shaped reinforcing body creation method of the present embodiment includes a connection process (step S1), a press-fitting process (step S2), an injection process (step S3), a removal process (step S4), and a foundation formation process (step S5). Contains.

  The connecting step (step S1) is a step of connecting the pile head 1a of the expandable steel pipe pile 1 and the injection head 2 to each other.

  The expanded steel pipe pile 1 is one in which both ends of a steel deformed pipe having a concave cross section are sealed with sleeves. A sleeve at one end of the expandable steel pipe pile 1 constitutes a pile head 1a. The pile head 1 a is provided with an opening 1 b that communicates with the inside of the expandable steel pipe pile 1. The expansion type steel pipe pile 1 has an expansion groove 1c in which the peripheral wall of the expansion type steel pipe pile 1 is deformed so as to be recessed inward. When the pressure fluid is injected into the expandable steel pipe pile 1 through the opening 1b, the expansion groove 1c is expanded, and the expandable steel pipe pile 1 can be expanded in the radial direction. For example, high-pressure water can be used as the pressure fluid.

  The injection head 2 is an instrument for injecting a pressure fluid into the expanded steel pipe pile 1 through the opening 1b of the pile head 1a. A hose 3 for supplying pressure fluid to the injection head 2 is connected to the injection head 2. A specific configuration of the injection head 2 will be described later with reference to the drawings.

  A pile driver 5 is connected to the injection head 2 via an attachment 4. A specific configuration of the attachment 4 will be described later with reference to the drawings. In FIG. 1, only a part of the pile driver 5 is shown.

  The injection head 2 according to the present embodiment is suspended by a pile driving machine 5 via an attachment 4. The pile driver 5 can transport the injection head 2 to any position within the site. In this Embodiment, the pile head 1a of the expansion type steel pipe pile 1 and the injection head 2 are inserted by inserting the pile head 1a of the expansion type steel pipe pile 1 into the inside of the injection head 2 from the opening of the lower surface of the injection head 2. Are connected to each other.

  The pile driving machine 5 is a construction machine for press-fitting the expandable steel pipe pile 1 into the ground 6. The press-fitting here means that a pressure composed of at least one of a static load and a dynamic load is applied to the expanded steel pipe pile 1 to push the expanded steel pipe pile 1 into the ground 6. The expanded steel pipe pile 1 can be pushed into the ground 6 only by static load or dynamic load. Moreover, the expansion type steel pipe pile 1 can also be pushed into the ground 6 by further applying a dynamic load due to impact to the expansion type steel pipe pile 1 while applying a static load to the expansion type steel pipe pile 1.

  As will be described in detail later, the injection head 2 of the present embodiment is configured to hold an expandable steel pipe pile 1 connected to the injection head 2. In other words, the injection head 2 of the present embodiment prevents the expandable steel pipe pile 1 from dropping from the injection head 2 due to its own weight even if the expandable steel pipe pile 1 connected to the injection head 2 is not manually supported. It is configured to be able to. The pile driving machine 5 can transport the expanded steel pipe pile 1 suspended through the injection head 2 to an arbitrary position in the site.

  The press-fitting step (step S2) is a step of press-fitting the expandable steel pipe pile 1 into the ground 6 in a state where the pile head 1a and the injection head 2 are connected to each other after the connecting step (step S1). The expandable steel pipe pile 1 may be press-fitted into the ground 6 so that the pile head 1a remains on the ground, but the expandable steel pipe pile 1 is placed on the ground 6 until the pile head 1a and the injection head 2 are located in the ground. Can be press-fitted. That is, in the pile-shaped reinforcing body creation method of the present embodiment, the injection head 2 can be pressed into the ground 6 together with the expandable steel pipe pile 1.

  An injection | pouring process (step S3) is a process of inject | pouring a pressure fluid into the inside of the expansion type steel pipe pile 1 through the injection | pouring head 2 after a press injection process (step S2). By injecting the pressure fluid into the expandable steel pipe pile 1, the expansion groove 1c is expanded and the expandable steel pipe pile 1 is expanded in the radial direction.

  The removal process (step S4) is a process of removing the injection head 2 from the pile head 1a of the expandable steel pipe pile 1 after the injection process (step S3). That is, in the pile-shaped reinforcing body creation method of the present embodiment, only the expanded steel pipe pile 1 is left on the ground 6.

  A foundation formation process (step S5) is a process of forming the foundation 7 on the pile head 1a while performing root cutting after an injection | pouring process (step S3).

  2 is a cross-sectional view of the injection head 2 of FIG. 1, FIG. 3 is a plan view showing the injection head 2 of FIG. 2, and FIG. 4 is a bottom view of the injection head 2 of FIG. Although the thing of arbitrary structures can be used as the injection | pouring head 2, it is especially useful to use the injection | pouring head 2 shown in FIGS. 2-4 for the pile-shaped reinforcement body preparation method of this Embodiment. . As shown in FIG. 2, the injection head 2 of the present embodiment includes a head body 20, an inner plug 21, a hose connection joint 22, a first annular packing 23, a spacer ring 24, a second annular packing 25, and a holding mechanism 26. Is provided.

  The head body 20 is a cylindrical member. The injection head 2 is press-fitted into the ground 6 (see FIG. 1) with the lower surface 200 of the head body 20 as a tip. A lower outer peripheral surface of the head main body 20 is a tapered surface 201 having a tapered shape. That is, the injection head 2 of the present embodiment is configured such that the lower part of the head body 20 is tapered, and the resistance when being pressed into the ground 6 can be reduced.

  A through-hole 203 that penetrates between the lower surface 200 and the upper surface 202 of the head main body 20 is provided inside the head main body 20. The lower part of the through-hole 203 opens in the lower surface 200 of the head main body 20, and comprises the pile head insertion hole 203a for the pile head 1a of the expansion type steel pipe pile 1 to be inserted. The pile head 1 a of the expandable steel pipe pile 1 is inserted into the pile head insertion hole 203 a through the opening of the lower surface 200 of the head body 20. The upper part of the through-hole 203 is opened in the upper surface 202 of the head body 20 and constitutes an inner plug insertion hole 203b for inserting the inner plug 21.

  A lower inner peripheral wall 204, an intermediate inner peripheral wall 205, and an upper inner peripheral wall 206 are provided inside the head body 20. The lower inner peripheral wall 204 is provided at the lower portion of the head body 20 and extends inside the intermediate inner peripheral wall 205 and the upper inner peripheral wall 206 with respect to the radial direction 203 c of the through hole 203. The intermediate inner peripheral wall 205 is provided on the upper part of the lower inner peripheral wall 204, and extends on the inner side of the upper inner peripheral wall 206 and on the outer side of the lower inner peripheral wall 204 with respect to the radial direction 203 c of the through hole 203. The upper inner peripheral wall 206 is provided on the upper part of the intermediate inner peripheral wall 205, and extends outside the lower inner peripheral wall 204 and the intermediate inner peripheral wall 205 with respect to the radial direction 203 c of the through hole 203. A first step 204 a is formed between the lower inner peripheral wall 204 and the intermediate inner peripheral wall 205, and a second step 205 a is formed between the intermediate inner peripheral wall 205 and the upper inner peripheral wall 206.

  The inner plug 21 of the present embodiment is a substantially cylindrical member having a recess 21a on the end surface. The inner plug 21 is inserted into the inner plug insertion hole 203b through the opening of the upper surface 202 of the head body 20 so that the recess 21a faces downward. The pile head 1 a of the expandable steel pipe pile 1 is inserted into the recess 21 a of the inner plug 21. The lower end of the inner plug 21 is in contact with the second step portion 205a.

  The outer peripheral surface of the inner plug 21 is configured by a curved surface parallel to the upper inner peripheral wall 206 as a whole. The inner plug 21 of the present embodiment is inserted inside the head body 20 so as to be able to advance and retract. Here, the term “advanceable / retractable” means a state in which the inner plug 21 can be easily advanced / retracted by pushing or pulling the inner plug 21 in the extending direction 203 d of the through-hole 203. In other words, the inner plug 21 of the present embodiment is not screwed into the head body 20. A groove in which a packing is fitted is formed on the outer peripheral surface of the inner plug 21.

  As particularly shown in FIG. 3, a plurality of fastening holes 207 are provided on the upper surface 202 of the head body 20 at intervals in the circumferential direction 203 e of the through holes 203. The attachment 4 is connected to the upper surface 202 of the head body 20 by attaching a fastening member such as a bolt to the fastening hole 207 in a state where the attachment 4 is superimposed on the upper surface 202 of the head body 20. By connecting the attachment 4 to the upper surface 202 of the head main body 20, the inner plug 21 is held between the attachment 4 and the second step portion 205a. The attachment 4 of this embodiment also serves as an upper lid for holding the inner plug 21. A member different from the attachment 4 may be used as an upper lid for holding the inner plug 21.

  The hose connection joint 22 is a portion to which a hose 3 for supplying pressure fluid to the injection head 2 is connected. As shown in FIG. 2, the hose connection joint 22 of the present embodiment is located in the upper surface 202 when the upper surface 202 of the head main body 20 is viewed along the extending direction 203d of the through hole 203 (pile head insertion hole 203a). It extends from the upper surface 202 so as to be positioned. In other words, the hose connection joint 22 does not protrude from the upper surface 202 of the head body 20 with respect to the radial direction 203 c of the through hole 203. As described above with reference to FIG. 1, the hose connection joint 22 extends from the upper surface 202, so that when the injection head 2 is press-fitted into the ground 6 together with the expandable steel pipe pile 1, the hose connection joint The possibility that 22 is damaged is reduced.

  As shown in FIG. 2, a flow path 22 a communicating with the hose connection joint 22 is provided inside the head body 20. The flow path 22a extends downward from the hose connection joint 22 along the extending direction 203d of the through hole 203, extends in the radial direction 203c of the through hole 203 inside the intermediate portion inner peripheral wall 205, and opens at the intermediate portion inner peripheral wall 205. ing.

  The first annular packing 23, the spacer ring 24, and the second annular packing 25 are sandwiched between the first step portion 204 a in the head body 20 and the lower end of the inner plug 21. The spacer ring 24 is arranged so as to face the groove 1d of the pile head 1a inserted into the pile head insertion hole 203a. The groove portion 1 d is provided with an opening portion 1 b that communicates with the inside of the expandable steel pipe pile 1. The first and second annular packings 23 and 25 are arranged so as to sandwich the spacer ring 24, and are in close contact with the peripheral wall of the pile head 1a on both sides of the groove portion 1d of the pile head 1a inserted into the pile head insertion hole 203a. Are arranged to be.

  The spacer ring 24 is provided with a plurality of discharge holes 240 spaced from each other in the circumferential direction of the spacer ring 24. The intervals between the discharge holes 240 are preferably equal. Between the back surface of the spacer ring 24 and the intermediate inner peripheral wall 205 of the head main body 20, an annular gap portion 241 communicating with the flow path 22 a from the hose connection joint 22 is provided. The fluid supplied to the injection head 2 through the hose 3 and the hose connection joint 22 is filled in the gap 241 and discharged from the discharge hole 240. When the pile head 1a is inserted into the pile head insertion hole 203a of the injection head 2, the fluid discharged from the discharge hole 240 is injected into the expandable steel pipe pile 1 through the opening 1b of the pile head 1a.

  The holding mechanism 26 is a mechanism that is engaged with the pile head 1a inserted into the pile head insertion hole 203a and holds the pile head 1a in the pile head insertion hole 203a. The configuration of the holding mechanism 26 is arbitrary, but the holding mechanism 26 of the present embodiment is configured by a plurality of ball plungers 260 built in the lower portion of the head body 20.

  As particularly shown in FIG. 4, the ball plungers 260 are arranged at intervals in the circumferential direction 203 e of the through hole 203 (pile head insertion hole 203 a). The tip 260 a of the ball plunger 260 protrudes from the lower inner peripheral wall 204 into the pile head insertion hole 203 a and can advance and retreat in the radial direction 203 c of the through hole 203 so as to be hidden inside the lower inner peripheral wall 204. . As particularly shown in FIG. 2, when the tip 260a of the ball plunger 260 enters the lower part of the pile head 1a inserted into the pile head insertion hole 203a, each ball plunger 260 enters the pile head insertion hole 203a. The pile head 1a is held in the pile head insertion hole 203a by being engaged with the inserted pile head 1a.

  5 is a front view showing the attachment 4 of FIG. 1, and FIG. 6 is a bottom view showing the attachment 4 of FIG. As shown in FIG. 5, the attachment 4 is provided with a lower flange 40, a cylinder portion 41, an upper flange 42, and a prism portion 43. The lower flange 40, the cylinder portion 41, the upper flange 42, and the prism portion 43 are joined together.

  The lower flange 40 is a disk-like portion disposed at the lower portion of the attachment 4 and is a portion that is overlapped with the upper surface 202 of the head body 20 described above. As particularly shown in FIG. 6, the lower flange 40 is provided with a plurality of fastening holes 400 spaced apart from each other in the circumferential direction of the lower flange 40. When the attachment 4 is connected to the upper surface 202 of the head body 20 as described above, a fastening member such as a bolt is passed through the fastening hole 400 of the lower flange 40.

  Further, the lower flange 40 is provided with a notch 401 through which the hose connection joint 22 is inserted when the lower flange 40 is superimposed on the upper surface 202 of the head main body 20. By providing the notch 401 in the lower flange 40, interference between the lower flange 40 and the hose connection joint 22 is avoided.

  The cylinder portion 41 is a cylinder member disposed on the upper portion of the lower flange 40. The upper flange 42 is a disk-shaped portion provided on the upper portion of the cylindrical portion 41. The prism portion 43 is a prism portion provided on the upper portion of the upper flange 42. A through-hole 430 that can be used for connection with the pile driving machine 5 is provided in the prism portion 43. In addition, tapered surfaces 431 are provided at the four outer corners of the prism portion 43. Further, a protrusion 432 protrudes from the lower part of the prism portion 43, and this protrusion 432 passes through the upper flange 42 and is inserted inside the cylinder portion 41.

  In such a pile-shaped reinforcing body creation method, the pile head 1a and the injection head 2 are connected to each other after the connection step of connecting the pile head 1a and the injection head 2 of the expandable steel pipe pile 1 to each other. In the state, it includes a press-fitting process for press-fitting the expanded steel pipe pile 1 into the ground 6 and an injection process for injecting a pressure fluid into the expanded steel pipe pile 1 through the injection head 2 after the press-fitting process. The construction period can be shortened in an environment where additional work is required for installation. This configuration is particularly useful for soft ground and ground with a high groundwater surface.

  Further, the hose connection joint 22 extends from the upper surface 202 of the head main body 20 so as to be positioned in the upper surface 202 when the upper surface 202 of the head main body 20 is viewed along the extending direction 203d of the through hole 203 (pile head insertion hole 203a). Since it is extended, the possibility of damaging the hose connection joint 22 when the injection head 2 is press-fitted into the ground 6 together with the expanded steel pipe pile 1 can be reduced, and additional work is required to attach the injection head 2 more securely. The construction period can be shortened in the resulting environment.

  Further, an inner plug 21 is inserted into the inside of the head main body 20 through an opening provided in the upper surface 202 of the head main body 20 so as to freely advance and retract, and an inner plug is interposed between the second step portion 205 a in the head main body 20 and the attachment 4. Since the plug 21 is configured to be held, it is possible to reduce the possibility that the inner plug 21 and the head main body 20 are damaged by the pressure at the time of press-fitting as compared with an aspect in which the inner plug 21 is screwed to the head main body 20. The construction period can be shortened in an environment where additional work is required to attach the injection head 2 more reliably.

  Furthermore, since the attachment 4 for connecting the injection head 2 to the pile driving machine 5 also serves as an upper lid for holding the inner plug 21, the number of parts can be reduced.

  Moreover, since the holding mechanism 26 holds the pile head 1a in the pile head insertion hole 203a, it is possible to prevent the expandable steel pipe pile 1 from falling off after the injection head 2 is attached to the pile head 1a of the expandable steel pipe pile. The construction period can be shortened in an environment where additional work is required to attach the injection head 2 more reliably.

  Further, the injection head 2 is suspended by a pile driving machine 5 and the pile head 1a of the expandable steel pipe pile 1 is inserted into the injection head 2 through the opening on the lower surface of the injection head 2, thereby expanding the steel pipe. Since the pile head 1a of the pile 1 and the injection head 2 are connected to each other, the connection between the pile head 1a of the expandable steel pipe pile 1 and the injection head 2 can be performed more easily. The construction period can be shortened in an environment where additional work is required for installation.

  Furthermore, since the pile driving machine 5 can transport the injection head 2, the handling of the injection head 2 can be facilitated. Particularly, in the case where the pile head 1a can be held by the holding mechanism 26, the expansion steel pipe pile 1 can be transported more easily together with the injection head 2, and the construction period in an environment where additional work is required to attach the injection head 2 more reliably. Can be shortened.

DESCRIPTION OF SYMBOLS 1 Expandable steel pipe pile 1a Pile head 2 Injection head 20 Head main body 200 Lower surface 202 Upper surface 203a Pile head insertion hole 21 Inner plug 22 Hose connection joint 26 Holding mechanism 4 Attachment 5 Pile driver 6 Ground

Claims (10)

A connection process for connecting the pile head and the injection head of the expanded steel pipe pile to each other;
After the connecting step, a press-fitting step of press-fitting the expanded steel pipe pile into the ground with the pile head and the injection head being connected to each other;
After the press-fitting step, an injection step of injecting a pressure fluid into the expanded steel pipe pile through the injection head;
Removing the injection head from the pile head,
How to make a pile-shaped reinforcement. The injection head is
The head body,
Pile head insertion hole for being provided in the head main body so as to open on the lower surface of the head main body,
A hose connection joint extending from the upper surface so as to be located in the upper surface when the upper surface of the head body is viewed along the extending direction of the pile head insertion hole,
The pile-shaped reinforcement body preparation method of Claim 1. The injection head is
A cylindrical head body having a stepped portion inside;
An inner plug that is inserted into the inside of the head body so as to freely advance and retreat from an opening provided on the upper surface of the head body,
By connecting an upper lid to the upper surface of the head body, the inner plug is held between the upper lid and the stepped portion.
The pile-shaped reinforcement body creation method of Claim 1 or Claim 2. The upper lid also serves as an attachment for connecting the injection head to a pile driver,
The pile-shaped reinforcement production method of Claim 3. The injection head is
The head body,
Pile head insertion hole for being provided in the head main body so as to open on the lower surface of the head main body,
It is engaged with the pile head inserted in the pile head insertion hole, and has a holding mechanism for holding the pile head in the pile head insertion hole,
The pile-shaped reinforcement body preparation method as described in any one of Claim 1- Claim 4. In the connecting step, the injection head is suspended by a pile driving machine, and the pile head of the expandable steel pipe pile is inserted into the injection head from the opening on the lower surface of the injection head, The pile head of the expandable steel pipe pile and the injection head are connected to each other;
The pile-shaped reinforcement body preparation method as described in any one of Claim 1- Claim 5. The pile driver can carry the injection head,
The pile-shaped reinforcement production method of Claim 6. An injection head connected to a pile head of an expanded steel pipe pile, for injecting pressure fluid into the expanded steel pipe pile,
The head body,
Pile head insertion hole for being provided in the head main body so as to open on the lower surface of the head main body,
An injection head comprising: a hose connection joint extending from the upper surface so as to be located in the upper surface when the upper surface of the head main body is viewed along the extending direction of the pile head insertion hole. An injection head connected to a pile head of an expanded steel pipe pile, for injecting pressure fluid into the expanded steel pipe pile,
A cylindrical head body having a stepped portion inside;
An inner plug inserted into the inside of the head main body so as to freely advance and retract from an opening provided on the upper surface of the head main body,
By connecting an upper lid to the upper surface of the head body, the inner plug is held between the upper lid and the stepped portion.
Injection head. An injection head connected to a pile head of an expanded steel pipe pile, for injecting pressure fluid into the expanded steel pipe pile,
The head body,
Pile head insertion hole for being provided in the head main body so as to open on the lower surface of the head main body,
An injection head, comprising: a holding mechanism that is engaged with the pile head inserted into the pile head insertion hole and holds the pile head within the pile head insertion hole.