KR20190143205A - Construction method of composite pile with extensioned tip - Google Patents

Abstract

The present invention relates to a construction method of a composite pile with an expanded bulb, which is capable of construction without being influenced by a stiffening state of an expanded bulb formed on a lower portion of a perforation hole by pre-constructing a pile main body and is possible to prevent subsidence of the pile by fixing the pile main body by principal surface friction. The construction method of a composite pile with an expanded bulb of the present invention includes: a step (a) of embedding a pile main body formed with a hollow into a perforation hole of the ground; a step (b) of forming solidification on a space between the pile main body and the perforation hole and fixing the pile main body to an inner wall of the perforation wall by principal surface friction; and a step (c) of forming an expanded bulb on a lower portion of the pile main body.

Description

Construction method of composite pile with extensioned tip

The present invention can be installed without being influenced by the hardening state of the enlarged bulb formed in the lower portion of the drilling hole by pre-installing the pile body, and the enlarged bulb is formed to fix the pile body by the main surface friction force to prevent the settlement of the pile It is about file construction method.

In pile construction for construction of various construction and civil structures, in order to increase the tip bearing capacity, the bottom of the drilling hole is enlarged to form an enlarged bulb, and then the pile is fixed to fix the tip of the pile in the enlarged bulb.

In the above method, the drilling hole is first formed in the ground, and the filling material is filled in the lower portion of the drilling hole to form an enlarged bulb, and then the construction is performed in the order of entering the pile before the enlarged bulb is completely hardened.

However, since the magnified bulb is located below the drill hole, it is difficult to check whether the magnified bulb is cured to an appropriate level to enter the pile. In addition, there is a problem that the settlement of the pile continuously occurs until the enlarged bulb is completely cured after the pile ingress.

Further, as disclosed in Korean Patent Laid-Open Publication No. 10-2010-0026486, after forming a pile hole, that is, a drilling hole in the ground, the pile main body is pushed into the pile hole by press-in or driving, and then the pile lower portion is excavated by excavating means. There is a method of expanding and digging and filling the filler to form an enlarged foundation.

However, the above technique requires a separate indentation equipment or driving equipment because the pile body is pushed into the pile hole by pressing or driving, and a lot of time is required for the driving of the pile body. In addition, since the inner diameter of the pile ball and the outer diameter of the pile body do not coincide exactly, there is a loss in the main surface friction force between the pile body and the pile ball. In addition, since the inner wall of the pile hole is relaxed by the tip of the pile body during the press-fitting or driving process of the pile body, the main surface friction force of the pile body cannot be expected, and there is a disadvantage in that it depends only on the tip bearing force of the enlarged foundation part.

In addition, such a prior art has to expand and excavate the lower portion of the pile body by a separate excavating means that can be expanded and then insert the injection material by inserting the injection tube for filling the filling material. Therefore, the burden of equipment is increased and the construction period is increased, and an additional slime discharge process is required for the expansion foundation excavation.

In order to solve the above problems, the present invention is to provide a composite pile construction method in which the enlarged bulb can be formed without being affected by the hardening state of the enlarged bulb is formed in the lower portion of the drilling hole by pre-construction.

An object of the present invention is to provide a composite pile construction method in which an enlarged bulb capable of preventing settlement of a pile by fixing a pile body by a main surface frictional force.

The present invention is to provide a complex pile construction method is formed with an enlarged bulb that can be improved in the construction is simple, thereby improving the economics by reducing the construction period.

According to a preferred embodiment of the present invention, the method includes: (a) integrating a pile main body in which a hollow is formed into a drilling hole of a ground; (b) forming a solid body in a space between the pile body and the drilling hole to fix the pile body to the inner wall of the drilling hole by a main surface friction force; And (c) forming an enlarged bulb at the bottom of the pile body; It provides a composite pile construction method formed with an enlarged bulb characterized in that the configuration.

According to another preferred embodiment of the present invention, the step (a) is to form a drill hole in the ground, and then, the hollow is formed in the drill hole, and the step (b) is between the drill hole and the outer peripheral surface of the pile body. Provided is a composite pile construction method in which a magnified bulb is formed, wherein the pile body is fixed to the inner wall of the drilled hole by the main surface frictional force through the hardened solid by injecting and curing the injection material.

According to another preferred embodiment of the present invention, the step (a) rotates the injecting equipment into the pile construction point of the ground to relax the soil in the ground to the set depth, and sprays the gelling agent with the stirring equipment to relax the soil. And gelling the soil by agitation of the gelling agent to form a loose earth stalk, and then form a hollow body in the loose earth stalk, and the step (b) is performed through the solidified body in which the loose earth stalk is cured. Provided is a composite pile construction method in which an enlarged bulb is formed, wherein the pile body is fixed to the inner wall of the drilling hole by a main surface friction force.

According to another preferred embodiment of the present invention, the step (c) includes: (c1) inserting a jet grouting device having a jet nozzle at the tip of the high-pressure jet rod into the hollow of the pile body; (c2) forming an enlarged bulb at a lower portion of the pile body by high-pressure spraying the injection material with the injection nozzle of the jet grouting equipment; And (c3) removing the jet grouting equipment; It provides a composite file construction method formed with a magnified bulb comprising a.

According to another exemplary embodiment of the present invention, there is provided a method of constructing a composite file having an enlarged bulb, wherein an enlarged portion having an enlarged diameter is protruded to the outside of the enlarged bulb.

According to the present invention has the following effects.

First, since the solid body is provided between the pile body and the drilling hole to be pre-formed before the enlarged bulb is formed, the pile body is fixed in the drilling hole by the main surface friction force. As a result, the enlarged bulb can be formed in the state in which the pile body is fixed to the inner wall of the hole, so that the pile body can be prevented from sinking during the enlarged bulb forming operation.

Second, since the tip of the pile body is supported by the enlarged bulb and is not influenced by the slime under the hole, the slime discharge operation can be omitted after the hole drilling.

Third, when the pile body is infiltrated and then hardened in the loose soil body formed by stirring the loosened soil and gelling agent while excavating the ground by the excavation stirring equipment, the pile body can be immediately accessed by gelling the ground. Therefore, no separate soil removal work is required, which shortens the construction stage and greatly shortens the construction time.

Fourth, if the enlarged bulb is formed by jet grouting can minimize the drilling diameter to significantly reduce the air, there is no need to use a large excavation equipment to form the enlarged bulb. In addition, since the crushed peripheral ground is mixed with the injection material, a separate slime treatment process is omitted.

1 is a view showing the construction sequence according to an embodiment of the composite pile construction method of the present invention enlarged bulb.
2 is a view showing a construction sequence according to another embodiment of the composite pile construction method in which the enlarged bulb of the present invention is formed.
3 is a view showing a process of forming an enlarged bulb by the jet grouting equipment.
4 is a view showing a composite file including an enlarged bulb in which an enlarged portion is formed;

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings and preferred embodiments.

1 is a view showing the construction sequence according to an embodiment of the composite pile construction method in which the enlarged bulb of the present invention is formed.

As shown in (a) to (e) of FIG. 1, the composite pile construction method in which the enlarged bulb is formed of the present invention includes (a) drilling holes (1) of the pile body (2) on which the hollows (21) are formed. 11) entering in; (b) forming a solid body 12 in a space between the pile main body 2 and the drilling hole 11 to fix the pile main body 2 to the inner wall of the drilling hole 11 by a main surface friction force; And (c) forming an enlarged bulb (3) in the lower portion of the pile body (2); Characterized in that consists of.

The present invention can be applied without being affected by the hardened state of the enlarged bulb 3 by pre-installing the pile main body 2 before forming the enlarged bulb 3 in the lower portion, and fix the pile main body 2 by the main surface friction force. The present invention provides a composite pile construction method in which magnified bulbs are formed that can prevent settlement of piles.

In the composite pile construction method in which the enlarged bulb of the present invention is formed, first, (a) the pile main body 2 having the hollow 21 is inserted into the drilling hole 11 of the ground 1 (FIG. 1B).

The pile body 2 is a reinforcing member for increasing the bearing capacity of the composite pile, and has a different purpose from the casing provided for protecting the wall of the drilling hole 11.

The pile body 2 may be used as long as the pile 21 has a hollow 21 formed therein, such as a PHC pile and a steel pipe pile.

Next, (b) a solid body 12 is formed in the space between the pile main body 2 and the drilling hole 11 to fix the pile main body 2 to the inner wall of the drilling hole 11 by the main surface frictional force. (D) of FIG. 1, (c) The enlarged bulb 3 is formed in the lower part of the said pile main body 2 (FIG. 1 (e)).

In the step (b), since the solid body 12 is provided between the pile main body 2 and the drilling hole 11, the pile main body 2 is fixed in the drilling hole 11 by the main surface frictional force.

That is, the enlarged bulb 3 may be formed in the lower portion of the pile main body 2 in a state in which the pile main body 2 is fixed to the inner wall of the drilling hole 11. As a result, the pile main body 2 can be prevented from being settled during the enlargement bulb 3 forming operation.

In other words, since the slime of the lower part of the drilling hole 11 is not completely removed, the general embedded pile has settled in the pile body 2 over time after the pile body 2 is inserted into the drilling hole 11. Occurs. In contrast, in the present invention, in the state in which the pile main body 2 is fixed to the side by the main surface frictional force, an enlarged bulb 3 for supporting and fixing the tip of the pile main body 2 is formed under the pile main body 2. Therefore, long term settlement of the pile main body 2 can be prevented.

In the case of using the present invention, the tip of the pile body 2 is ultimately supported by the enlarged bulb 3 and is not affected by the slime under the hole of the hole 11, and thus the slime discharge operation after the hole of the hole 11 is omitted. can do.

In the step (a), after forming the drilling hole 11 in the ground 1, the pile body 2 having the hollow 21 is formed in the drilling hole 11, and the step (b) is the drilling hole ( It is possible to fix the pile main body 2 to the inner wall of the drilling hole 11 by the main surface frictional force through the solidified body 12 which is hardened by injecting and curing the injection material 12a between the 11 and the outer peripheral surface of the pile main body 2. Can be.

This is for the embodiment in which the pile main body 2 is inserted after the drilling hole 11 is bored.

In the step (a), after drilling a hole 11 having a diameter larger than that of the pile main body 2 in the ground 1 as shown in FIG. 1 (a), the hole is drilled as shown in FIG. The pile main body 2 can be mounted in the drilling hole 11.

In the step (b), as shown in (c) of FIG. 1, an injection material 12a such as mortar is injected into a space between the drilling hole 11 and the outer circumferential surface of the pile main body 2 to be cured.

Accordingly, the pile body 2 is fixed by the punching hole 11 and the main surface frictional force through the solidified body 12 formed by curing the injection material 12a.

2 is a view showing a construction sequence according to another embodiment of the composite pile construction method of the present invention enlarged bulb.

As shown in (a) to (e) of Figure 2, the step (a) is the rotational penetration of the stirring equipment at the pile construction point of the ground (1) while relaxing the soil in the ground (1) to the set depth, The gelling agent is sprayed with the stirring equipment to agitate the loosened soil and the gelling agent to gel the soil, thereby forming a loose soil body 12b, and then a hollow 21 is formed in the loose soil body 12b. The pile main body 2 is mounted, and the step (b) is to fix the pile main body 2 to the inner wall of the drilled hole 11 by frictional force through the solidified body 12 on which the loose earth and sand bodies 12b are cured. can do.

This does not puncture the ground (1) without drilling, the ground (1) excavation and stirring proceeds at the same time to form a loose soil body (12b) is formed inside the drill hole (11) and then the loose soil body (12b) The present invention relates to an embodiment in which the pile main body 2 freely falls in and closes in ().

In the step (a) while rotating the penetration of the stirring equipment to the pile construction point of the ground (1) while relaxing the soil in the ground (1) to the set depth, by spraying the gelling agent with the stirring equipment to loosen the soil and gelling agent By stirring, the earth and sand are gelled to form the loose soil body 12b.

2 (a) shows the process of excavating and stirring the ground (1) by the excavation stirrer (5), Figure 2 (b) is shown a state in which the formation of the loose soil body (12b) is completed. .

Thereafter, as shown in FIG. 2C, the pile main body 2 in which the hollow 21 is formed in the loose soil body 12b is incorporated.

In this case, excavation and stirring equipment (5) can be made at the same time excavation of the ground (1) and agitation of the soil and gelling agent. Therefore, it is possible to access the pile main body 2 immediately by gelling the ground 1, thus eliminating the need for soil removal, thereby reducing the construction stage and greatly reducing the construction time.

And, as shown in (d) of FIG. 2, in the step (b), the pile main body 2 is provided on the inner wall of the drilling hole 11 by the frictional force through the solidified body 12 on which the loose earth and sand bodies 12b are cured. Can be fixed

Finally, as shown in FIG. 2E, the step (c) of forming the enlarged bulb 3 in the lower part of the pile main body 2 is performed.

When the gelling agent is mixed with the soil in the perforation hole 11, the soil is temporarily in a gel state. In the step (a), after the pile main body 2 is incorporated in the loose soil body 12b, the loose soil body 12b. ) Is cured again to form a solid 12. Accordingly, the pile main body 2 can be fixed by the inner wall of the drilling hole 11 and the main surface frictional force.

On the other hand, when the pile main body 2 is approached in the step (a), a part of the gelled loose soil body 12b may be introduced into the hollow 21 in the pile main body 2. However, since the pile main body 2 enters into the loosening soil body 12b by the free fall, the amount of the loosening soil body 12b flowing into the hollow 21 by the air pressure in the hollow 21 is only slight.

In addition, the lower portion of the hollow 21 of the pile body 2 may be blocked by solidified soil. However, when high-pressure compressed air or compressed air and ultra-high pressure water are injected from the injection nozzle 42 of the jet grinder 4 to be described later, there is a problem in puncturing the solidified soil located inside the hollow 21 of the pile body 2. none.

3 is a diagram illustrating a process of forming an enlarged bulb by a jet grouting apparatus.

As shown in (a) to (d) of FIG. 3, the step (c) of forming the enlarged bulb 3 in the lower portion of the pile main body 2 is (c1) at the tip of the high-pressure jet rod 41. Inserting the jet grouting equipment (4) equipped with the injection nozzle (42) into the hollow (21) of the pile body (2); (c2) forming an enlarged bulb (3) in the lower portion of the pile main body (2) by high-pressure spraying the injection material (12a) with the injection nozzle (42) of the jet grinder (4); And (c3) removing the jet grouting equipment (4); It may be configured to include.

In this case, as shown in (a) of FIG. 3, after (c1) the jet grouting equipment 4 is inserted into the hollow 21 of the pile main body 2 through the hollow 21 of the pile main body 2, As shown in FIG. 3 (b), the small-diameter drilling hole 13 having a predetermined depth is excavated in the lower portion of the hollow 21 by the jet grouting equipment 4.

Next, as shown in (c) of FIG. 3, (c2) a high-pressure injection of the injection material 12a into the injection nozzle 42 of the jet grouting equipment 4 to enlarge the bulb 3 in the lower portion of the pile main body 2 To form.

The enlarged bulb (3) is formed by the injection material (12a) is injected at a very high pressure from the lower portion of the small diameter hole (13).

Then, as shown in (d) of Figure 3, (c3) to remove the jet grouting equipment (4).

When the jet grouting equipment 4 is removed in the step (c3) and the jet grouting equipment 4 is pulled out while filling the injection material inside the hollow 21 of the pile main body 2, the cross section of the pile main body 2 is removed. Reinforcement can increase the bearing capacity.

In the step (c) of the present invention shown in FIG. 3, the peripheral ground 1 is cut downward from the front end of the pile main body 2, and the injection material 12a is injected and filled to form an enlarged bulb 3. Draw and remove grouting equipment (4).

In particular, in step (c2), the injection material 12a, such as cement milk, is supplied through the high-pressure jet rod 41 of the jet grouting equipment 4, and the compressed air is injected at a very high pressure through the injection nozzle 42, the surrounding ground Directly crush (1). At the same time, the crushed soil and the injection material 12a are mixed and cured to form a cylindrical enlarged bulb 3.

Accordingly, the diameter of the excavation can be minimized, so that the enlarged bulb 3 can be formed directly, thereby greatly reducing the air, and it is not necessary to use a large excavation equipment to form the enlarged bulb 3.

In addition, since the crushed peripheral ground 1 is mixed with the injection material 12a, a separate slime process is omitted during the enlarged bulb 3 forming operation. That is, when the injection material 12a or the like is injected from the injection nozzle 42 by high pressure, the slime at the tip of the pile body 2 as well as the surrounding ground 1 is mixed with the injection material 12a and cured, so that the hole 11 is formed. No need for slime removal at the bottom

In addition, since the enlarged bulb (3) is formed by jet grouting, it is advantageous for downtown construction due to less vibration and noise, and it can be installed in the city with small equipment.

According to the present invention, the lower portion may form an enlarged bulb 3 by jet grouting, thereby improving and expanding the ground 1 of the tip of the pile, thereby maximizing the tip bearing force. And the upper part is secured by the frictional force of the main surface of the pile body (2), so it is possible to construct an economical composite pile.

4 is a diagram illustrating a composite file including an enlarged bulb in which an enlarged portion is formed.

As shown in FIG. 4, an enlarged portion 31 having a diameter enlarged outward may protrude from an upper portion of the enlarged bulb 3.

The upper part of the enlarged bulb 3 in which the tip of the pile main body 2 is fixed, the load of the pile main body 2 is concentrated and stress concentration may occur.

Therefore, when the enlarged portion 31 having an enlarged diameter is formed on the enlarged bulb 3, the stress of the pile body 2 can be distributed to the large area of the enlarged bulb 3, so that It is possible to prevent stress concentration occurring near the tip.

In addition, the enlarged portion 31 increases the end support area of the composite pile by increasing the end support area. And by transmitting the stress in multiple stages to the lower ground (1) it is possible to effectively distribute the load of the composite pile to the ground (1).

1: ground
11: drilling hole
12: solid
12a: injection material
12b: Relaxation bodies
13: Small Diameter Hole
2: file body
21: hollow
3: enlarge bulb
31: enlarged portion
4: jet grouting equipment
41: high pressure jet rod
42: injection nozzle
5: Excavation Stirring Equipment

Claims (5)

(a) inserting the pile body 2 having the hollow 21 into the drilling hole 11 of the ground 1;
(b) forming a solid body (12) in the space between the pile body (2) and the drilling hole (11) to fix the pile body (2) to the inner wall of the drilling hole (11) by a major friction; And
(c) forming an enlarged bulb (3) in the lower portion of the pile body (2); Composite file construction method formed with an enlarged bulb, characterized in that consisting of.
In claim 1,
In the step (a), after forming the drilling holes 11 in the ground 1, the pile body 2 in which the hollow 21 is formed in the drilling holes 11 is entered,
In the step (b), the injection hole 12 and the outer circumferential surface of the pile main body 2 are injected and cured to inject and cure the pile main body 2 through the solidified body 12. The composite pile construction method with enlarged bulbs, characterized in that fixed to the inner wall of the main surface by the frictional force.
In claim 1,
In the step (a), the infiltration of agitating equipment into the pile construction point of the ground (1) rotates and loosens the soil in the ground (1) to a predetermined depth, while spraying a gelling agent with the stirring equipment to relax the soil and the gelling agent. After stirring, the earth and sand were gelled to form a loose sand body 12b, and then the pile body 2 in which the hollow 21 was formed was inserted in the loose sand body 12b.
In the step (b), the enlarged bulb is formed by fixing the pile main body 2 to the inner wall of the drilling hole 11 by the frictional force through the solidified body 12 on which the loosening earth body 12b is cured. Compound file construction method.
In claim 1,
Step (c) is
(c1) inserting the jet grouting equipment 4 having the injection nozzle 42 at the tip of the high-pressure jet rod 41 into the hollow 21 of the pile body 2;
(c2) forming an enlarged bulb (3) in the lower part of the pile main body (2) by high-pressure spraying the injection material (12a) with the injection nozzle (42) of the jet grinder (4); And
(c3) removing the jet grouting equipment (4); Composite file construction method formed with an enlarged bulb comprising a.
In claim 1,
The enlarged bulb (3) in the upper portion of the enlarged portion (31) is enlarged outwardly enlarged portion (31) characterized in that the enlarged bulb formed composite pile construction method.

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