JP2789370B2 - Piling method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Prior Art> Instead of a method of directly driving a pile, a method of inserting the pile into a hole drilled in the ground has been developed.

<Problems to be Solved by the Present Invention> Such a prior boring method has a feature that the problem of noise and vibration is solved as compared with the driving method.

However, there is a drawback that the supporting force is lower than that of the driving method.

That is, since the boring hole having a diameter equal to or slightly smaller than the diameter of the pile is drilled in advance, a phenomenon in which the frictional force on the peripheral surface is reduced is inevitable.

Therefore, the outer diameter of the pile in design was limited to the outer shape of the pile itself.

<Object of the present invention> The present invention has been made in order to improve the above-mentioned problems, and does not generate impact vibration or noise. It is an object of the present invention to provide a method of placing a pile, which can be wider than the pile.

<Means for Solving the Problems> That is, in the present invention, a hole is drilled in the ground, a hollow pile is inserted into the hole, and the hardening material is pressed into the hole through the hollow portion of the pile. This is a method of placing a pile, in which the hardened material in the pressurized state is injected and penetrated into the ground around the hole.

<Description of the Present Invention> Hereinafter, the present invention will be described in detail.

<B> Drilling A predetermined hole 1 is drilled in the ground of the target area using an earth auger or the like.

The inner diameter of the hole 1 is substantially equal to the outer diameter of the hollow pile 2 to be built.

In the figure, the gap between the hollow pile 2 and the hole 1 is drawn large, in order to make the explanation of the injection situation easy to understand.

<B> Hollow pile It is the hollow pile 2 to be built in the hole 1.

This hollow pile 2 can be used whether it is a steel pipe or a concrete pipe.

 The hole at the center of the hollow pile 2 is formed as an injection hole 21.

 The injection hole 21 is formed in a vertically penetrating state.

Therefore, the lower end of the injection hole 21 opens at the tip of the hollow pile 2, while the upper end of the injection hole 21 opens above the hollow pile 2.

The hardening material 4 is injected from the outside into the injection hole 21 at a high pressure through this opening.

For this purpose, a thread or the like for attaching a valve is formed at the upper end of the injection hole 21.

<C> Installation of Hollow Pile A pressure pump P of a hardening material 4 is connected via a hose 3 to the upper portion of the hollow pile 2 having the above structure.

And a hollow pile 2 having an outer diameter substantially the same as the inner diameter of the hole 2
Is once lifted and inserted into the hole 1 by its own weight.

After insertion to a certain depth, the pump P is operated to supply the hardening material 4 such as cement milk or mortar from the injection hole 21 of the hollow pile 2 and discharge it into the hole 1 from the opening at the tip.

Therefore, a slight gap around the hollow pile 2 is hardened material 4
Will be filled. In this case, it is not necessary to inject at a high pressure.

In order to obtain the same effect, a method of first filling the hole 1 with the hardening material 4 such as mortar, and then inserting the pile 2 may be employed.

<D> Pressurization around the periphery After the hardening material 4 is filled around the hollow pile 2 and before the hardening material 4 is hardened, the hardening material 4 is injected at a high pressure through the injection hole 21 this time.

Then, due to the pressure, the hardening material 4 penetrates from the tip of the hollow pile 2 to the surrounding ground and expands.

Therefore, high adhesion between the pile and the ground can be achieved, and an effective pile body can be formed.

Injection of the high-pressure hardening material 4 does not normally cause backflow of the hardening material 4 from the opening of the hole 1.

Because the outer diameter of the hollow pile 2 and the inner diameter of the hole 1 are almost the same or only a few percent larger,
This is because the hardening material 4 injected from the front end is clogged by itself in the process of ascending, and a seal packer effect is obtained.

<E> Another embodiment It is also possible to open slits 5 at a plurality of locations around the hollow pile 2.

Then the hardening material 4 such as cement milk from the slit 5
However, not only at the tip of the hollow pile 2 but also at the middle or upper position where it is particularly desired to harden due to the geological relationship, it penetrates into the surrounding ground, so that more effective frictional resistance can be obtained.

In the case of such a hollow pile 2 of the slit opening type, a case where the hardening material 4 flows backward from the opening of the hole 1 is also assumed.

In that case, an inflatable sealing material may be attached annularly around the upper portion of the hollow pile 2.

After installing the hollow pile 2 on the ground by a series of operations, it is also possible to construct a high-strength composite pile by inserting structural members such as reinforcing steel and H steel into the hollow pile 2 and filling the hardening material. It is.

<Effects of the present invention> The present invention is a method for driving a pile in the above-described steps, and therefore the following effects can be achieved.

<B> There is a general pile at the center, and a structure in which the ground around the general pile is integrated with the general pile can be obtained.

Therefore, it is possible to make the design pile diameter larger than the actual pile diameter.

 Therefore, an extremely economical pile can be obtained.

<B> A method of forming a pile of hardened material 4 in the ground using a special device such as a jet has already been developed and is being used on site.

However, the method of the present invention does not require such a special device, and a pile constituted by the hardening material 4 can be constructed underground with a simple device.

<C> Since the method is not a method that involves hitting, there is no generation of vibration or noise, and construction is possible in urban areas.

[Brief description of the drawings]

 FIG. 1 to FIG. 4 are explanatory views showing the construction order of the present invention.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E02D 5/54 E02D 3/12 101

Claims (1)

(57) [Claims] A hole is drilled in the ground, a hollow pile is inserted into the hole, and a hardening material is injected into the hole through the hollow portion of the pile by pressurizing, and the hardening material is injected into the ground around the hole. Pile driving method