JP2881615B2 - Device to prevent squirting of cement during construction of earth anchor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for preventing the ejection of a solidified material during earth anchoring.

[0002]

2. Description of the Related Art Earth anchors are generally constructed by drilling.
Injection of solidification material → steel wire insertion → pulling out of casing, pressure injection of solidification material → tension and fixing. The drilling is performed by attaching a bit to the tip of the casing pipe and rotating it while adding the casing pipe, and removing the casing pipe while leaving the bit in the ground. Is carried out while removing each one.

When the casing pipe is pulled out, a consolidated material is injected into the hole through the pipe under pressure. At this time, the compacted material is removed from the pipe tail when the casing pipe is removed. Attempts to squirt from the end. So conventionally,
Using a grouting packer or the like as shown in FIGS.

[0004] Fig. 3 shows an example in which an earth anchor is used as a support for the retaining wall a. A constantly expanding grouting packer c is attached to the tail end of the steel wire b inserted into the hole.
Is installed. The casing pipes d1 to d4 are connected to each other by connecting portions e including male screw portions and female screw portions provided at both ends of each pipe.

[0005] The casing pipe d is withdrawn while a solidifying material f such as cementite is injected under pressure from the tail end.
At this time, since the grouting packer c contracts due to the injection pressure, injection becomes possible. After the connection portion e is pulled out until it exceeds the grouting packer c, as shown in FIG. 4, the pressurization injection is stopped, and the casing pipe d1 is removed from the connection portion e. At this time, since the injection pressure does not act on the grouting packer c, the grouting packer c returns to the expanded state, and closes the inside of the tail end of the casing pipe d2, so that the ejection of the consolidated material f can be prevented.

[0006]

SUMMARY OF THE INVENTION The above prior arts include:
The following problems exist. That is, the casing pipe d is usually formed thin except for the connecting portion e, and if there is a convex portion on the outer peripheral surface side, it becomes a resistance at the time of pulling out, so that the connecting portion e is protruded toward the inner peripheral surface side. Shape. Therefore, when the casing pipe d is pulled out, the connecting portion e may get caught on the grouting packer c, and the grouting packer c may be damaged.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and it is intended to prevent breakage of a casing pipe when the casing pipe is pulled out and to reliably prevent ejection of a consolidated material. It is an object of the present invention to provide a device for preventing a solidified material from being ejected during construction of an earth anchor.

[0008]

That is, the present invention is directed to a method for solidifying a compaction material into a hole through a pipe while pulling out a casing pipe for drilling a hole in an earth anchor. An apparatus for preventing a binder from spouting from the tail end of a casing pipe, wherein the binder has an outer diameter smaller than the inner diameter of the casing pipe, and at least the outer diameter of the casing pipe is smaller than that between the connecting portions at both ends of the casing pipe. A tubular body having a long axial length, and at least the connecting portion mounted in the circumferential direction on the outer peripheral surface of the tubular body and spaced apart from the axial length of the connecting portion in the axial direction of the tubular body. A ring-shaped water blocking body having an outer diameter larger than the inner diameter of the connecting portion and having elasticity, and a solidification provided at a tail end of the pipe body; Characterized in that it comprises means for connecting to a material injection device. Lanka - a caking material blowout preventer apparatus during construction. Further, in the above-described apparatus for preventing a binder from spouting when the earth anchor is constructed, a fixing plate having a flow hole for the binder and an insertion hole for the anchor steel wire is attached to the pipe body, and the anchor steel wire is provided. The anchor is inserted into the insertion hole so as to anchor the pipe to the anchor steel wire so as not to move in the direction of the tail end.
This is a device for preventing the ejection of consolidated material during construction.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS.
An embodiment of the ejection prevention device 100 of the present invention will be described. The same members as those in FIGS. 3 and 4 of the related art are denoted by the same reference numerals, and description thereof will be omitted.

<A> Tube 110 in the figure is a normal tube having both ends opened.
110 has an outer diameter smaller than the inner diameter of the connecting portion e of the casing pipe d, and has an axial length longer than at least the length L1 between the connecting portions e at both ends of the casing pipe d. .

<B> Water Stopper A thick portion 111 is provided on the outer peripheral surface of the tube 110 in the circumferential direction, and a water stop 12 is provided in a groove recessed in the center of the thick portion 111 in the circumferential direction.
0 is attached. The water stopping body 120 is provided with a casing pipe d.
Is an annular body having an outer diameter larger than the inner diameter of the connecting portion e, and made of an elastic material such as rubber.

In addition, the water stopping body 120 is spaced apart from the inner length L2 of the inner surface of the connecting portion e by an interval shorter than at least the length L1 between the connecting portions e in the axial direction of the tube 110. Deploy multiple over.

<C> Injecting device connecting means At the tail end of the tube 110, connecting means for connecting the injecting device of the consolidated material f is provided. For example, a structure in which a cap 130 is screwed to the tail end of the tube 110 and a connecting pipe 131 is attached to the center of the cap 130 is conceivable. In addition, various other structures can be adopted as the connecting means.

<D> Tube Fixing Means A fixing plate 140 having a flow hole 141 for the consolidated material f and an insertion hole 142 for the steel wire b is mounted in the tail end of the tube 110.
The steel wire b is inserted into the insertion hole 142 and fixed with a wedge 143 or the like, so that the tube 110 is moored to the steel wire b so as not to move toward the tail end. The pipe 110 can be fixed not only to the steel wire b but also to a drilling machine main body for performing a drawing operation and other places.

[0015]

The spout preventing device 100 is attached to the tail end of the steel wire b by the above-described method, and the steel wire b is inserted into the casing pipe d which has been drilled. A connecting material injection hose 300 is connected to a connecting pipe 131 at the tail end of the squirt prevention device 100 via a tick valve 200 having a check valve structure.

The casing pipe d is drawn by an excavator or the like, and at the same time as the drawing, a consolidated material f such as cement milk is drawn.
Is injected under pressure into the hole through the casing pipe d. The consolidation material f enters the cap 130 from the connecting pipe 131, passes through the flow hole 141 of the fixing plate 140 and the inside of the tube 110, and is injected into the hole from the open end of the tube 110.

Then, as shown in FIG. 1, the pressure injection of the consolidated material f is stopped, and the connecting portion e of the casing pipes d1 and d2 is pulled out until reaching the tail end of the ejection preventing device 100. After that, the casing pipe d1 is removed from the connecting portion e.
At this time, the water stopping body 120 is pressed against the inner surface of the connecting portion e on the tip side of the casing pipe d2, and the gap between the inner surface of the casing pipe d2 and the outer surface of the tube 110 is closed. The consolidated material f does not erupt from the tail end.

The inner surface of the connecting portion e and the inner surface of the raised portion g of the casing pipe d shown in FIG.
The frictional resistance generated between the casing pipe d and the water stopping body 120 when the casing pipe d is pulled out can be reduced. Therefore, the adhesion between the water stopping body 120 and the inner surface of the connecting portion e is enhanced, and the water stopping effect can be improved.
Can be smoothly extracted.

After removing the casing pipe d1,
The casing pipe d2 is similarly pulled out and removed. At this time, the connecting portion e on the distal end side of the casing pipe d2 moves to the tail end side. However, since the mounting interval of the water stopping body 120 is shorter than the axial length of the inner surface of the connecting portion e, the inner surface of the connecting portion e is Always has the water stop 120 crimped. Therefore, the gap between the inner surface of the casing pipe d2 and the outer surface of the pipe 110 is always closed, and the consolidated material f does not blow out from the tail end of the casing pipe d2.

After the removal of the casing pipe d2, the casing pipe d is similarly pulled out and removed up to the end in the same manner as at d3, d4,..., And the case pipe removal step is completed.

[0021]

Since the present invention has been described above,
The following effects can be obtained. <B> Since the elastic body such as rubber is used for the water stopping body, it does not break even if the connecting portion hits when the casing pipe is pulled out, and it is possible to reliably prevent the ejection of the consolidated material. it can.

<B> Since the tube has a simple structure in which a waterproof body such as a rubber ring is attached to the outer peripheral surface of the tube, the production cost and the maintenance cost are low.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an enlarged explanatory view of a main part.

FIG. 3 is an explanatory view of a conventional technique.

FIG. 4 is an explanatory view of a conventional technique.

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) E02D 5/80

Claims (2)

(57) [Claims] When a compaction material is injected into a hole through a pipe while pulling a casing pipe for drilling an earth anchor, the compaction material is formed at the tail end of the casing pipe. A device for preventing ejection from the part, having an outer diameter smaller than the inner diameter of the casing pipe;
And a pipe having an axial length longer than at least the connecting portions at both ends of the casing pipe; and a circumferentially mounted outer circumferential surface of the pipe and having an interval shorter than the axial length of the connecting portion. A plurality of annular waterstops having an outer diameter larger than the inner diameter of the connecting portion and having an outer diameter greater than an inner diameter of the connecting portion, the plurality of waterstops being provided in a range longer than at least the length between the connecting portions in the axial direction of the pipe; A device for preventing the ejection of a consolidated material at the time of earth anchoring, comprising a connecting means for connecting to a consolidated material injection device provided at a tail end of the tubular body. 2. A fixing plate according to claim 1, wherein a flow hole for the bonding material and an insertion hole for the anchor steel wire are opened in the pipe body. The pipe is anchored to the anchor steel wire so that it does not move in the direction of the tail end by inserting an anchor steel wire into the insertion hole and fixing it.
Sunker-A device to prevent squirting of cement during construction.