JPS6126429Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a temporary drag pile (for example, an anchor or a suspended pile) that is used to temporarily absorb loads and pull-out reaction forces during various types of construction work, and is removed after the work is completed. In particular, the present invention relates to a temporary drag pile equipped with an elastic bag that is inflated by injection of pressurized fluid as a drag body against loading or pulling force.

Conventionally, a drag pile whose drag body is an elastic bag that expands when fluid is press-fitted has a rubber membrane bag that expands into a spherical shape at the tip, and a rubber membrane bag with the deepest part of the bag at the tip. The anchor pile has a structure in which reinforcing bars connected by strings are inserted into a mortar injection pipe, and the opening of the bag body is connected to the tip of the mortar injection pipe so that mortar is press-fitted from the injection pipe, that is, the rubber membrane It is known that a bulbous anchor body is created in the ground by inflating a bag body by press-fitting mortar to form an anchor body, which is cast in place with mortar. The reality is that an effective and appropriate temporary drag pile that can be used as a drag body against loading and pulling forces has not yet been materialized.

Incidentally, in order to convert the conventional anchor pile to a temporary drag pile, instead of press-fitting mortar into the rubber membrane bag, pressurized fluid (generally Even if compressed air is used, in this conventional anchor pile, the rubber film bag is supported at two points, the mouth of the bag and the deepest part, at the tip of the mortar injection pipe and the tip of the reinforcing bar. Because it is supported at the bottom, the connection to the mortar injection pipe and reinforcing bars lacks stability, and if the ground around the bag is soft and contains localized hard parts such as stones, the bag will Caught by the local hard part, the reinforcing bar is prevented from expanding uniformly around the axis of the reinforcing bar, and expands toward the opposite side of the local hard part with respect to the axis, It is not possible to form a drag body that effectively supports or anchors the entire circumferential surface of the pile.

Therefore, even in the case of soft ground where hard parts such as stones are mixed locally, the present invention has been developed to effectively spread the elastic bag around the pile body by injecting pressurized fluid into the ground, without causing the elastic bag body to shift to one side. The aim is to provide a temporary drag pile that can be expanded uniformly and effectively.

To explain the drawings, the temporary drag pile of the present invention has a pile main body 1 made of a rigid rod-like body, and an elastic bag body 2 that expands when pressurized fluid is injected and contracts due to the pressure drop of the fluid, which creates a drag force against the loading or pulling force. The elastic bag body 2 is a temporary drag pile provided with a body, and the elastic bag body 2 is
The elastic bag 2 has an annular and hollow shape that surrounds the outer peripheral surface of the pile body 1, and its inner peripheral surface is fixed to the outer peripheral surface of the pile body 1. Although it may be a single bag in the direction (the type shown in Figure 1), it is more preferable to have a bag divided into several pieces (the type shown in Figure 3). With this latter type, pressurized fluid can be injected into each divided bag at the optimal pressure to match the geological unevenness of the pile construction site, making it possible to better adjust the pile construction conditions. Further, it is preferable that the elastic bag body 2 is arranged in multiple stages in the length direction of the pile body 1 in order to obtain a stronger resistance pile. In the figure, reference numerals 3 and 4 are passages for supplying pressurized fluid to the elastic bag body 2. In order to inject the pressurized fluid into the elastic bag 2, instead of using the channel shown in the figure, there is a method that extends in the length direction of the wall of the pile body 1 and communicates with the elastic bag 2, or a type that communicates with the elastic bag 2 through the wall of the pile body 1. A type with a horizontally penetrating hole and a pipe connected to the hole and fixed to the inner surface of the pile body 1, a type in which the pile body 1 is a solid body and a pipe communicating with the elastic bag body 2 is fixed to the outer surface, and a solid pile body. This may also be done by drilling holes that connect to the elastic bag 2.

According to the present invention, when the pile body 1 with the elastic bag body 2 is inserted into the pile hole 4 having a slightly larger diameter and pressurized fluid is injected into the elastic bag body 2, the elastic bag body 2 It is expanded by the fluid and acts as a resisting force against the loading or pulling force applied to the pile body 1, and the expansion consolidates the ground around the pile hole 4 and hardens it.

During the above expansion, the elastic bag 2 is annular and hollow surrounding the outer circumferential surface of the pile main body 1, and its inner circumferential surface is fixed to the outer circumferential surface of the pile main body 1.
The pile body 1, which is a rigid rod-shaped body, is used as a base and is expanded only to the surrounding area. Therefore, the pile construction site is on soft ground and hard parts such as stones are locally mixed therein. Even if there are
Only the part corresponding to the local hard part is prevented from expanding as shown in FIG. 4, and the elastic bag body 2 as a whole is
is guaranteed to inflate substantially uniformly around the pile body 1 without shifting, thus ensuring that the elastic bladder 2
The drag body obtained by the expansion achieves an effective mounting or anchoring effect.

Since the present invention has the above-mentioned effects, the pile of the present invention erected in the ground can be used as an anchor pile,
This is particularly suitable when the pile 6 is press-fitted by a static loading type pile press-fitting machine 7 (FIG. 5).

In the present invention, the elastic bag 2 contracts when the pressure of the pressurized fluid inside the elastic bag 2 is lowered, so after the required construction work is completed, the pile body 1 can be easily removed from the pile hole 4 by contracting the elastic bag 2. and can be recovered.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing one embodiment of the present invention, Fig. 2 is a vertical cross-sectional view thereof, Fig. 3 is a transverse cross-sectional view showing another embodiment of the invention, and Fig. 4 shows the inflated state of the elastic bag. FIG. 5 is a vertical cross-sectional view showing an example of the use of the pile of the present invention. 1 is the pile body, 2 is the elastic bag body.

Claims (1)

[Scope of utility model registration request] A temporary drag pile in which a resisting body against mounting or pulling force is provided on a pile main body made of a rigid rod-like body, which is made of an elastic bag body that expands when pressurized fluid is injected and contracts due to the pressure drop of the fluid, wherein the above-mentioned elastic bag A temporary drag pile whose body is annular and hollow surrounding the outer circumferential surface of a pile body, and whose inner circumferential surface is fixed to the outer circumferential surface of the pile body.