JP5948068B2 - Pile construction method with anchors - Google Patents

Description

  The present invention relates to a pile construction method using an anchor in combination. More specifically, the present invention relates to an improvement in a pre-boring method for a ready-made pile such as a concrete pile, a steel pipe concrete pile, and a steel pipe pile.

  In order to improve the pulling-out strength of a pile constructed in the ground, a construction method of installing an anchor in the pile has been proposed. In addition, in such a construction method, a method has been proposed in which the anchor is not contacted with the cement cured body so that the anchor does not adversely affect the cement cured body on the circumferential surface of the pile (see, for example, Patent Document 1).

JP 2007-239420 A

  However, in the construction method as in Patent Document 1, the following problems are caused because a pre-made pile that is hollow and has a closed end is used. That is, (1) When a ready-made pile is sunk, buoyancy acts on the pile, so that water must be poured into the hollow portion in order to suppress this, and therefore there is also a need to drain after that. (2) When an anchor is inserted into a ready-made pile, in order to guide the tip (lower end) of the anchor to the center of the tip of the pile, a guide that tilts in a bowl shape around the center is necessary. (3) If a hole is made in the cement structure after solidification so as to form a passage through which the anchor is inserted, the expression strength as the cement structure may be impaired.

  Therefore, the present invention is based on various problems in the prior art, there is no drainage process, there is no need to provide an anchor guide on the pile, and the anchor strength that can secure the expression strength of the cement structure can be secured. It aims at providing the construction method of the pile which used together.

  The present invention, which has been conceived by the present inventor in order to solve such problems, is a cylindrical pile in which the ground is pre-bored, a hardening agent is introduced into a drilling hole by the pre-boring, and both ends are opened, and the pile A cylindrical guide pipe disposed inside is built in the excavation hole, an anchor is inserted into the guide pipe, and the anchor is constructed.

  In the construction method according to the present invention, since a cylindrical pile having both ends opened at both the distal end and the proximal end is used, the pile can be laid without any buoyancy acting thereon. For this reason, it is not necessary to put water into the hollow part of a pile, and it is not necessary to drain.

  Moreover, in the construction method according to the present invention, a guide pipe built inside the pile is used, and the anchor is installed inside the pile by inserting the anchor through the guide pipe. Therefore, it is not necessary to provide a guide on the pile.

  Furthermore, in the construction method according to the present invention, the anchor may be inserted into the guide tube after the hardening agent is solidified, and it is not necessary to make an anchor insertion hole in the cement structure after solidification. For this reason, it is easy to ensure the expression strength of the cement structure after solidification.

  In such a construction method, the pile and the guide pipe can be integrated and built in the excavation hole. Alternatively, the pile can be built in the excavation hole first, and then the guide tube can be built in the pile.

  Moreover, in such a construction method, it is preferable to use a guide tube in which an anti-sway member that suppresses the shake of the guide tube is formed.

  It is also preferable to build the guide tube into the excavation hole with the tip of the guide tube blocked. In this case, it is more preferable that the closed end of the guide tube is punched out with a drill and the anchor is inserted through the guide tube.

  According to the present invention, it is possible to eliminate the drainage process, make it unnecessary to provide anchor guides on the pile, and secure the expression strength of the cement structure.

It is a figure which shows the process until it excavates the ground and builds a pile in an excavation hole in order of (A)-(D). It is a figure which shows the process from the place where a guide pipe | tube is built to forming an anchor fixing | fixed part following FIG. 1 in order of (E)-(H). FIG. 3 is a diagram illustrating steps from the construction of the guide tube to the formation of the anchor fixing portion in the order of (I) to (J) following FIG. 2.

  Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

  1 to 3 show an embodiment of a pile construction method using an anchor according to the present invention. In the construction method according to the present invention, the ground G is pre-bored, the hardeners 5 and 6 are put into the excavation hole 4 by the pre-boring, and the cylindrical pile 1 having both ends opened, and the pile 1 are disposed in the pile 1. The cylindrical guide tube 3 is built in the excavation hole 4, and after the hardened materials 5 and 6 are solidified, the anchor 2 is inserted into the guide tube 3 and the anchor 2 is installed. Specific examples of the pile 1 include cylindrical ready-made piles whose both ends and base ends are open, such as concrete piles, steel pipe concrete piles, steel pipe piles, and the like.

  In FIG. 1 etc., the code | symbol 11 is an excavation rod for excavating the excavation hole 4 which is rotationally driven by an auger motor (illustration omitted) and sinks the pile 1. FIG. A drill bit 12 is provided at the lower end of the drill rod 11.

  The excavation rod 11 has a hollow structure and also serves as a pipe for passing a liquid or the like. When this excavation rod 11 excavates in advance, air, water, excavation liquid, etc. are ejected from the lower end nozzle. Moreover, the excavation blade 13 is provided in the lower end part of the excavation bit 12 (refer FIG. 1).

  A state in which the ground G is pre-bored using the excavation rod 11 and the excavation bit 12 and the pile 1 and the anchor 2 are constructed in the excavation hole 4 is shown below (see FIG. 1A, etc.).

  First, the shaft core of the excavation bit 12 provided at the lower end of the excavation rod 11 is aligned with the core position of the pile 1. Next, an auger motor (not shown) is rotated to rotate the excavation rod 11 and excavate the ground G to a predetermined depth.

  Thereafter, while moving the excavating rod 11 up and down, a rooting liquid 5 such as cement milk is supplied to the internal piping of the excavating rod 11 from a batcher plant (not shown) installed on the ground. Then, a root hardening liquid 5 is injected into the excavation hole 4 from the nozzle at the tip of the pipe to form a root hardening part (root hardening bulb). The cement milk illustrated here is only an example of a slurry for cement hardening body for root hardening, and other cement powder may be used. The cement powder can be mixed with water used during excavation or the like and water contained in the ground G to form a slurry. Further, it is desirable to stir the cement milk by raising and lowering the excavation bit 12 about three times during the injection of the cement milk.

  Then, the pile periphery fixing liquid 6 is inject | poured, pulling up the excavation bit 12 (refer FIG. 1 (B)). As the pile periphery fixing liquid 6, for example, cement milk can be used. In addition, as the pile circumference fixing liquid 6 and the above-described root hardening liquid 5, cement milk having the same composition (as an example, a water cement ratio of 60%) can be used. However, in the present embodiment, 70 to 100% of the excavation volume is injected for the root hardening liquid 5, and 10 to 30% of the excavation volume is injected for the pile circumference fixing liquid 6 to solidify the root. The liquid 5 has a higher strength after solidification.

  When the excavation bit 12 is pulled up from the excavation hole 4 (see FIG. 1 (C)), the pile 1 is built to a predetermined depth and set (see FIG. 1 (D)). The piles 1 are laid while a plurality of piles 1 are successively connected as necessary.

  Next, the guide tube 3 is built into the inside (hollow part) of the pile 1 (see FIG. 2E). In the present embodiment, the guide tube 3 having a closed end is employed, and the guide tube 3 is built into the excavation hole 4 from the closed end. In such a case, the root hardening liquid 5 and the pile circumference fixing liquid 6 injected into the excavation hole 4 do not enter the guide pipe 3.

  Moreover, if the steadying member 7 which suppresses the shake of the guide tube 3 is formed in the pile 1 or the guide tube 3, the guide tube 3 is restrained from being shaken and the shaft core of the guide tube 3 is attached to the shaft core of the pile. It is preferable because they can be combined. For example, in the present embodiment, a steady-state stabilization member 7 extending in the radial direction is provided on the outer peripheral surface of the guide tube 3, and the steady-state stabilization member 7 is brought into contact with the inner peripheral surface of the guide tube 3 to thereby prevent the guide tube 3 from shaking. (See FIG. 2E). The steadying member 7 is arranged at intervals of 120 degrees in, for example, three directions in the circumferential direction. These steadying members 7 are preferably arranged at two positions spaced apart from each other in the guide tube 3 in the axial direction (see FIG. 2E).

  After several days to several weeks have passed and the root hardening liquid 5 and the pile fixing liquid 6 have solidified, the roots around the pile head of the pile 1 are cut and the pile head is excavated (see FIG. 2 (F)). .

  Next, the drill 8 is inserted into the guide tube 3, the closed end of the guide tube 3 is punched out, and the anchor hole 41 is excavated to a predetermined depth (see FIG. 2G). At this time, in order to prevent the anchor hole 41 from collapsing, a casing (not shown) may be used for excavation. Next, a grout material is injected from the tip of the drill 8, and after the injection, the drill 8 is recovered. Thereafter, the connecting member 2a is inserted into the guide tube 3, and the tip portion is fixed to the grout material to form the anchor fixing portion 2b (see FIG. 2 (H)). Furthermore, you may inject | pour a grout material by pressure from the hollow part etc. which were provided in the connection member 2a as needed.

  Subsequently, a structure 50 made of concrete or the like is created on the pile head (see FIG. 3I). Thereafter, the anchor 2 inserted through the structure 50 is pulled, and the anchor 2 is fixed to the structure 50 with a nut 51 or the like (see FIG. 3J). As a result, the structure 50 is supported by the pile 1 and is fixed in a state of receiving a downward pulling force by the anchor 2.

  According to the construction method of the present embodiment described so far, there is no time for draining during construction. In other words, in the conventional construction method, when the ready-made piles are laid, buoyancy acts on the piles, so in order to suppress this, water has to be put into the hollow part, and then it has been necessary to drain it. On the other hand, in this embodiment, since the cylindrical pile 1 of both ends opening opened at both the distal end and the proximal end is adopted, buoyancy does not act on the pile 1 when set up (FIG. 1 ( D) etc.). Therefore, it is not necessary to put water into the hollow portion of the pile 1, and it is not necessary to drain water, so that the labor required for these operations is not required.

  In addition, in the conventional method, when inserting an anchor into a ready-made pile, a guide for guiding the tip (lower end) of the anchor to the center of the tip of the pile is necessary. For example, a part of the pile is thickened as a bowl shape. In the present embodiment, the guide tube 3 built inside the pile 1 is used, and the anchor (connecting member 2a) is inserted into the guide tube 3 in the present embodiment. There is no need to provide a guide on the pile 1. Therefore, the pile 1 having a simple shape with a uniform thickness can be used.

  And according to the above guide tubes 3, the edge of the anchor 2 and the pile 1 etc. can be made into the cut state. That is, the guide tube 3 covers the periphery of the connecting member 2a of the anchor 2 and keeps the root-setting liquid 5 and the pile circumference fixing liquid 6 and the connecting member 2a separated (FIG. 2 (F), ( G) etc.). As a result, the connecting member 2a of the anchor 2 is fixed to the anchor fixing portion 2a on the distal end (lower end) side and to the nut 51 on the proximal end (upper end) side, while being fixed with cement milk or the like between them. Not in contact. Therefore, the influence on the pile 1 due to the expansion and contraction of the anchor 2 can be eliminated. Moreover, sufficient pulling force by the anchor 2 can be applied to the structure 50, and the pulling-out strength of the pile 1 can be improved.

  Furthermore, in the construction method of the present embodiment using the guide tube 3 as described above, the connecting member of the anchor 2 can be obtained without drilling a hole in the root hardening liquid 5 and the pile fixing liquid 6 after solidification. A space for inserting 2a can be ensured (see FIGS. 2F and 2G). Therefore, it is easy to secure the expression strength of the cement structure after solidification, as compared with the conventional method in which holes are made in the root hardening liquid 5 and the pile circumference fixing liquid 6.

  The above-described embodiment is an example of a preferred embodiment of the present invention, but is not limited thereto, and various modifications can be made without departing from the scope of the present invention. For example, in each of the above-described embodiments, the pile 1 is built and set to a predetermined depth (see FIG. 1 (D)), and then the guide tube 3 is built inside the pile 1 (FIG. 2 ( In addition, the pile 1 and the guide pipe 3 can be integrated into the excavation hole 4.

  The present invention is suitable for application to pre-boring methods for ready-made piles such as concrete piles, steel pipe concrete piles, steel pipe piles and the like.

DESCRIPTION OF SYMBOLS 1 ... Pile 2 ... Anchor 3 ... Guide pipe 4 ... Drilling hole 5 ... Root hardening liquid (hardening agent)
6 ... Pile circumference fixing liquid (hardening agent)
7 ... rest member G ... ground

Claims (4)

Pre-boring the ground,
Put a hardener into the drilling hole by the pre-boring,
A tubular pile with the both ends being opened, when no write build a cylindrical guide tube disposed within該杭in the wellbore, as the guide tube, member stop shake suppressing deflection of the guide tube Using what is formed,
Like an anchor before the pile in the borehole, and then, only write built the guide tube in the該杭,
A method for constructing a pile using an anchor, wherein the anchor is inserted into the guide tube and the anchor is constructed. Said guide tube, characterized in that Tatekomu in the wellbore while being closed the distal end of the guide tube, the construction method of the pile in combination an anchor according to claim 1. Pre-boring the ground,
Put a hardener into the drilling hole by the pre-boring,
A tubular pile which opposite open ends, and a cylindrical guide tube disposed within該杭, while the said guide tube obtained by closing the tip of the guide tube, seen write built in the wellbore ,
A method for constructing a pile using an anchor , wherein the anchor is inserted into the guide tube and the anchor is constructed. The method for constructing a pile using the anchor according to claim 2 or 3 , wherein the anchor is inserted into the guide tube after the closed end of the guide tube is punched out with a drill.