JPH0788657B2 - How to install a sleeve pipe - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sleeve pipe erection method which is performed in a preceding stage when the ground is improved by applying a sleeve injection method.

Conventional technology and its problems The sleeve injection method is a sleeve pipe (outer pipe) in the ground.
Is an injection pipe, and an injection inner pipe equipped with a double packer is inserted into the injection pipe, and injection is performed at an arbitrary position.

Conventional sleeve pipe installation is shown in Fig. 10 (a) to (d).
100 mm up to the bottom of the injection range, as outlined in the procedure
After making holes in the casing pipes (a) around φ (see FIG. 10 (a)) and filling the seal grout (b) therein (see FIG. 10 (b)), the grout (b) It has been carried out by a method in which a sleeve pipe (c) is installed inside and then the casing pipe (a) is removed. However, the conventional installation method has a large number of steps and requires a large amount of manpower and time to remove the casing pipe (a), and improvement thereof has been desired.

The present invention has been made in view of such a demand.

Means for Solving the Problems The present invention relates to the screw shaft and the sleeve pipe inside thereof while drilling the ground by drilling guide of an auger head in a state where a sleeve pipe is preliminarily loaded in a hollow screw shaft of an earth auger. To a predetermined depth in the ground, then while filling the seal grout into the drilled hole from the lower end of the screw shaft, while leaving the sleeve pipe in the penetration position through the opening at the lower end of the screw shaft, The present invention relates to a method of constructing a sleeve pipe, which is characterized by gradually pulling it up to the ground.

Example An example of the present invention will be described below with reference to the accompanying drawings.

In the present invention, the earth auger (1) is applied as the drilling means. The earth auger (1) is elevated along the reader (3) while being mounted on the base mazine (2). The leader (3) operates the cylinder (4) and is appropriately undulated with the base end pivotal support (3a) as a fulcrum.

The earth auger (1) is equipped with a driving machine (5) which is moved up and down along with the reader (3) by applying a conventional method, and a rotary shaft (6) rotated by the driving machine (5) is hollow and has an upper part ( 6
A) projects upward from the drive machine (5), and a hollow screw shaft (7) of the same diameter is coaxially connected to the lower end. An auger head (8) is provided at the lower end of the screw shaft (7) so as to open an opening (7a) (see FIG. 9) at the lower end of the shaft. The holding rod (9) is attached to the upper end of the leader (3).
A clamp (10) for gripping (see FIG. 5) is attached in a laterally protruding shape so that the center of the clamp (10) coincides with the central axis of the earth auger (1).

When drilling the ground with the earth auger (1), the sleeve pipe (11) is charged into the hollow shafts (6) and (7) of the auger (1). As shown, it is convenient to carry out with the earth auger (1) and its reader (3) lying down.

The charging operation will be described with reference to FIGS. 1 and 2, and the sleeve pipe (11) is connected to the hollow rotary shaft (6) and the hollow rotary shaft (6) via the open clamp (10) as shown by an arrow in FIG. It is inserted into the hollow screw shaft (7) and the insertion is finished, leaving a part of the upper end. On the remaining upper end (11a),
As shown in detail in FIG. 8, a retaining ring (12) is fitted, and after the retaining ring (12) is fitted, the upper end of the hollow rotary shaft (6) is first screwed (12a). The screw pipe (11) is then screwed, and then set screw (13) is used to connect with the upper end (11a) of the sleeve pipe (11) to finish the preparation of the sleeve pipe (11).

The outer diameter of the sleeve pipe (11) is smaller than the inner diameters of the rotating shaft (6) and the screw shaft (7), and in the charged state, as shown in FIG. ) And a grout injection passageway (14) are formed. A swivel joint (15) is provided at the upper end of the rotating shaft (6) in order to appropriately supply grout into the injection passage (14). As shown in FIG. 8, the upper end of the injection passage (14) is closed by a flange (6b) protruding inward from the upper end of the rotary shaft (6).

After the sleeve pipe (11) has been charged, the cylinder (4) is actuated to raise the earth auger (1) and its leader (3) as shown in FIG. The sleeve pipe (11) may be prepared before the base machine (2) is carried into the construction site.

When installing the sleeve pipe (11), the ground is drilled by the operation of the earth auger (1) in the state shown in FIG. 3, and as the drilling is performed, the sleeve pipe inside the screw pipe (7) and the screw pipe (7) are drilled. (11) is penetrated into the ground to a specified depth. This state is shown in FIG. During drilling operation, the sleeve pipe (11) receives earth pressure from the lower end, but the pipe (11) at the upper end side passes through the threaded portion (12a) of the retaining ring (12) to the upper end of the rotating shaft (6). Since it is screw-coupled with, it is possible to sufficiently oppose the earth pressure received from the lower end, and it is possible to travel integrally with the screw shaft (7) in the ground.

After drilling, the sleeve ring (11) is removed by removing the retaining ring (12) so that the rotary shaft (6) and the screw shaft (7).
And the pipe (11) is pushed down through the presser rod (9) until its tip hits the bottom of the drilled hole (16) as shown in FIG. (9) is clamped at the upper end by a clamp (10). Furthermore, the injection passage (14) (see FIG. 8) in the rotary shaft (6) and the screw shaft (7) is connected to the swivel joint (15) of the upper bridge of the rotary shaft (6) and the liquid feed pump (19). ) Is connected to a grout storage tank (18) via a conduit (17).

In the state shown in FIG. 5, the liquid feed pump (19) is operated to move the grout from the storage tank (18) through the conduit (17), the swivel joint (15), and the injection passage (14) in order, and then the screw shaft (7). The ground auger (1) is gradually pulled up to the ground while the sleeve pipe (11) is left inside the drilled hole (16) while filling the drilled hole (16) from the lower end of the hole.

FIG. 6 shows the situation after the pulling up of the earth auger (1), in which the sleeve pipe (11) is inserted and installed in the grout (20) filled in the drilled hole (16). By facing and curing the grout (20) in this state,
As shown in the figure, the installation of the sleeve pipe (11) is completed.

After finishing the construction of the sleeve pipe (11), an inner pipe for injection (not shown) equipped with a double packer is inserted into the pipe (11), and after cracking and water pushing as usual, The grout is injected.

Effect According to the method of the present invention, by utilizing the hole drilled by the earth auger and the auger pulling from within the drilled hole, it is possible to install the sleeve pipe in the drilled hole and further perform grout filling.
The sleeve pipe can be built substantially in one step, and the work efficiency can be improved and the labor can be saved.

[Brief description of drawings]

1 to 7 are explanatory views showing one embodiment of the method of the present invention in the order of steps, FIG. 8 is a vertical sectional view showing an example of a coupling means of a sleeve pipe and a hollow rotary shaft, and FIG. 9 is a lower end of a screw shaft. FIG. 10 is an enlarged view of the part, and FIG. 10 is an explanatory view of the conventional method. In the figure, (1) is an earth auger, (2) is a base machine, (3) is a reader, (4) is a cylinder, (5) is a drive machine, (6) is a hollow rotary shaft, and (7) is Hollow screw shaft,
(8) is an auger head, (9) is a holding rod, (10) is a clamp, and (11) is a sleeve pipe.

Claims (1)

[Claims] 1. The earth auger hollow screw shaft is preliminarily charged with a sleeve pipe, and while drilling the ground by the auger head excavation guide, the screw shaft and the sleeve pipe inside the hole are drilled to a predetermined depth in the ground. Penetrate and then gradually pull up the screw shaft above the ground while filling the hole from the lower end of the screw shaft with the seal grout and leaving the sleeve pipe at the penetrating position through the opening at the lower end of the screw shaft. A method for installing a sleeve pipe, which is characterized in that