JPH047231Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a tip bit of a core pipe for an earth anchor or the like.

(Prior Art) A method of constructing an earth anchor using a pipe as a core material is known from Japanese Patent Laid-Open No. 191721/1983.

In this construction method, the grout is injected at the same time as the core pipe is driven, so the tip bit attached to the tip of the core pipe must be able to fully satisfy both the functions of soil excavation and grout injection.

Conventional advanced bits had room for improvement in these respects.

(Problems to be solved by the invention) The present invention solves the above-mentioned conventional problems, has sufficient strength, allows grout to be injected without destabilizing the ground during soil excavation, and the injected grout. The purpose of the present invention is to provide a tip bit for a core pipe for an earth anchor, etc., which can prevent dirt from entering the ground.

(Means for Solving the Problems) In order to achieve the above-mentioned objects, the present invention includes a mounting end that is screwed to the core pipe, a disc-shaped flange continuous to the tip of the mounting end, and a mounting end that is screwed to the core pipe. A plurality of blades protruding from the tip side of the flange and extending radially in the radial direction;
The present invention proposes a tip bit of a core pipe for an earth anchor, etc., which is provided in the blade and has a plurality of outlet passages that open at the back surface of the collar and communicate with the inlet passage in the attachment end.

(Function) The tip bit of the present invention has the configuration described in the claims of the utility model registration, and in particular, since the outlet passage is provided within the blade, grout can be injected without reducing the strength of the tip bit.

The tip bit of the present invention has the same configuration as above, and in particular, the outlet passage is opened at the back of the flange, so grout is injected backward from the back of the flange, and as a result, grout can be injected without destabilizing the ground. I can do it.

The tip bit of the present invention has the same structure as above, and in particular, since there is a flange at the rear of the blade, even if grout is injected while excavating with the blade, dirt will not get mixed into the grout.

The tip bit of the present invention has the same structure as above, and in particular, since it has a plurality of outlet passages, grout can be injected evenly.

(Example) The tip bit of a core pipe for an earth anchor or the like according to the present invention will be described below according to an example shown in the drawings.

FIG. 1 shows an earth anchor etc. in which the core pipe with a tip bit of the present invention is used, and the earth anchor A etc. are made by hardening grout 9 using the core pipe 1 as a reinforcing material.

2 to 5 show the tip bit 2, which is attached to the tip of the core pipe 1 by a screw connection.

That is, the tip bit 2 has a threaded mounting end 11.

A disk-shaped flange 4 is continuous to the tip of the attachment end 11, and a plurality of blades 10 extending radially in the radial direction are provided protruding from the tip side of the flange 4.

Inside the blade 10 (all or a plurality of blades) there is an inlet passage 3 that opens on the back side of the collar 4 and that is inside the mounting end 11.
An outlet passage 5 is provided which communicates with the.

The function of the tip bit of the core pipe for earth anchors, etc. of the present invention shown in the above embodiments will be explained together with the construction method for earth anchors, etc.

That is, as shown in FIG. 2, a tip bit 2 is fixed to the tip of the core pipe 1.

Next, the core pipe 1 is driven into the ground G by being hit, rotated, etc. by a driving device (not shown).

At the same time as this driving, grout 9 is injected into the core pipe 1.

The grout 9 flows from the core pipe 1 through the inlet passage 3 and outlet passage 5 of the tip bit 2 into the borehole 7 formed by the tip bit 2.

That is, since the grout 9 is injected from the back side of the collar part 4 into the drilled hole 7 at the same time as the blade 10 excavates, the grout 9 can be injected without destabilizing the ground.

Furthermore, since the flange 4 is located behind the blade 10, the blade 1
Even if the grout 9 is injected while excavating at zero, soil and sand are prevented from entering the grout 9.

(Effects of the invention) The embodiments of the tip bit of the core pipe for earth anchors and the like according to the invention are as described above, and the effects thereof are listed below.

(1) The tip bit of the present invention has the configuration described in the claims of the utility model registration, and in particular, since the outlet passage is provided within the blade, it is possible to inject grout without reducing the strength of the tip bit.

(2) The tip bit of the present invention has the same configuration as above, and in particular, since the outlet passage is opened at the back of the flange, the grout is injected backward from the back of the flange, and as a result, it does not destabilize the ground. Grout can be injected.

(3) The tip bit of the present invention has the same configuration as above, and in particular, since there is a flange at the rear of the blade, even if grout is injected while excavating with the blade, earth and sand will not get mixed into the grout.

(4) The tip bit of the present invention has the same configuration as above, and in particular, since it has a plurality of outlet passages, grout can be injected evenly.

[Brief explanation of the drawing]

Figure 1 is a conceptual diagram of an earth anchor etc. using the core pipe with the tip bit of the present invention, Figure 2 is a diagram showing the construction method of the same earth anchor, and Figure 3 is a plan view of the tip bit of the present invention. , FIG. 4 is a half-sectional front view of the same, and FIG. 5 is a bottom view of the same. 1... Core pipe, 2... Tip bit, 3... Inlet path, 4... Flange, 5... Outlet path, 6... Hose, 7... Drilling, 8... Cover, 9... Grout , 10...Blade, 11...Mounting end, A...Earth anchor, G...Ground.

Claims (1)

[Scope of utility model registration request] A mounting end screwed to the core pipe, a disc-shaped flange continuous to the tip of the flange, and a plurality of blades extending radially in the radial direction protruding from the tip of the flange. A tip bit of a core pipe for an earth anchor or the like, which is provided in the blade and has a plurality of outlet passages that open at the back surface of the collar and communicate with the inlet passage in the attachment end.