JPH0663230B2 - Tie rod - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a tie rod.

(Prior Art) Tie rods are used especially when excavating the ground.

The retaining walls at the digging edge are actually under pressure of the surrounding soil on either side of it so that they should be anchored in this soil to prevent its tilting towards the interior of the excavation. May become apparent.

For this reason, boring is carried out in the soil present in the retaining wall and beyond and by introducing into the boring hole a tie rod, which generally comprises an injection pipe, such as a strand assembly and a sleeved pipe, around the tie rod. The hole is cemented and the tie rod head is then fixed to the wall.

Furthermore, it is necessary to embed and wrap these tie rods in an airtight duct to prevent the strands from eroding the final tie rods or temporary tie rods in aggressive environments.

Therefore, it has been known to pre-embed the strand assembly in an airtight duct and leave the sleeved tube next to it. In the end zone of the tie rod or its anchoring zone, the duct used was a corrugated duct to ensure its adherence to the injected cement.

<Problems to be Solved by the Invention> In this method, the diameter of the boring becomes extremely large due to the relatively large strand assembly, and the bundle of strands is not centered in the boring hole. There was a flaw.

Similarly, a method of using a central injection tube and arranging strands around this tube and surrounding the assembly with corrugated ducts has also been proposed. The problem in this case is to match the opening of the injection pipe with the outside of the duct, which is only possible by using a side branch on the injection pipe that runs between the strands and outside the corrugated duct. is there.

This method therefore has the drawback of requiring expensive special parts.

The present invention aims to correct these drawbacks.

<Means for Solving the Problems> Therefore, an object of the present invention is to provide a tie rod including an injection pipe and a plurality of strands arranged around the pipe, in which each strand is individually in a corrugated duct in a fixing zone. And these ducts are in tie rods, which are characterized in that they are freely arranged around the injection tube.

Of course, spacers can be placed in some places to maintain the relative position of the strands entering the injection tube and duct, but no external duct surrounds the entire tie rod.

The injection of the boring holes is thus carried out directly from the injection pipe and through the strands each surrounded by its protective duct.

The strands may be pre-embedded in the duct prior to the installation of the tie rods, but this installation is difficult if one does not want to damage the pre-embedding cement.

Therefore, in a preferred embodiment of the invention, each of the corrugated ducts leads at its end to an airtight cap, which in turn leads to the end of the injection tube.

Therefore, the injection tube is first of all used to pre-embed the strands in the ducts by injecting a suitable cement into the end cap and re-elevating this cement in the individual ducts.

As a variant or in combination with this method, it is possible to provide a separate prefilling tube arranged in place of one of the strands entering the duct near the injection tube. At this time, each injection duct and the preliminary fitting tube communicate with the airtight cap at their ends.

To ensure that the strands can be properly pre-embedded in their individual ducts, connect each corrugated duct to a vent pipe in the upper part of the anchoring zone of the tie rods so that it communicates with the free air. Is possible.

In this case, the pre-implantation injection is carried out until the cement reappears at the head of the boring hole.

The invention also relates to an end cap for a tie rod as described above, which is closed at one of its ends and which is connected in a gas-tight manner to at least a corrugated duct and a tube for pre-embedding of a strand into the duct. The end cap is also characterized in that it comprises a casing which is a substantially rotating casing with a plug through which a leading tube like that can be applied. The preliminary embedding tube may be an embedding tube and / or a special tube.

A specific embodiment of the present invention will now be described by way of non-limiting example with reference to the accompanying drawings.

<Example> The tie rod shown in FIG. 1 includes a head portion 1 and a fixing portion 2 at its end portion in a known manner.

The part 1 is surrounded by a smooth duct 3 which makes it possible to prestress the tie rods 4 distributed around the sleeved tube 5.

Such tubes are well known and are generally made of plastic material and have regularly spaced orifices 6. At the level of these orifices, the elastic sleeve 7 forms an injection valve. The injection is performed using a double occluding device to isolate a portion of the tubing on either side of the sleeve to allow injection of cement at this level.

According to the invention, each strand 4 is individually arranged in a corrugated duct 8 which allows its isolation from the external environment and its anchoring in the injected cement. These ducts are arranged around the lower part of the pipe 5.

The tie rod is provided at its lower end with a cap 9 which is shown in detail in FIG.

The cap has a pointed casing 10, one end 11 of which is closed, the other end of which has a central leading tube 13 and a peripheral leading tube 14 arranged around it. Is equipped with. Note that these leading pipes are outside the plug. The leading tube 13 passes through the stopper 12 to the bottom 11 of the cap, and the cap 10 and the stopper 12
There is an orifice 15 surrounded by a sleeve 16 in the cavity formed by.

On the other hand, the leading pipe 14 is stopped at the level of the stopper 12.

The sleeved injection tube 5 is fitted at its end around the leading tube 13 and glued, while the duct 8 is fitted around and glued around the leading tube 14.

The strands 4 pass through the leading tube 14 leaving some play to allow the cement for pre-implantation into its duct.

In the example shown in the figures, one of the leading tubes 14a receives a single smooth tube 18 instead of the duct and its strands.

Finally, at its end opposite the cap 9 or at the beginning of the head part 1 of the tie rod, the duct 8 is
Is continuous up to the head end of the tie rod,
It is connected to the ventilation pipe 19.

Once the tie rods are installed in their boring holes, the strands 4 are pre-embedded in their ducts 8 by injecting cement through the orifices 15 of the leading tube 13 via the injection tube 5 or also through the tube 18. To be done.

The cement re-rises in the space 17 and then in the tie rods 8 and finally in the tubes 19 to the surface. Thus, we can be confident that the pre-embedding was done properly.

So-called tie rod embedding is then followed by sleeved tube 5
In the conventional manner. The embedding cement flows out of the orifice 6 between the ducts 8 and thus embeds each strand individually within the borehole.

It will be appreciated that various changes and modifications may be made to the above description without departing from the scope or spirit of the invention.

[Brief description of drawings]

FIG. 1 shows the fixing zone of a tie rod according to the invention. FIG. 2 is an enlarged sectional view taken along the line II-II in FIG. FIG. 3 is an axial cross-sectional view of the cap at the end of the tie rod. FIG. 4 is an axial cross-section of this cap connected to the end of a tie rod. 1 ... Head part, 2 ... Fixing zone 3 ... Smooth duct, 4 ... Tie rod 5 ... Sleeve tube, 6 ... Orifice 7 ... Elastic sleeve, 8 ... Corrugated duct 9 ... Cap 10 ... Pointed casing 11 …… Casing end, 12 …… Stopper 13 …… Center leading pipe, 14 …… Peripheral leading pipe 15 …… Orifice, 16 …… Sleeve 18 …… Preliminary embedding pipe 19 …… Ventilation pipe

Claims (6)

[Claims] 1. A tie rod comprising an injection tube (5) and a plurality of strands (4) arranged around the injection tube, each strand (4) being an individual corrugated duct within a fixing zone (2). A tie rod housed in (8), wherein the corrugated duct (8) is arranged in a non-housing state around the injection tube (5). 2. Each corrugated duct (8) is in communication with the inside of the airtight cap (9) at each end and in communication with the airtight cap (9) at the end of the injection pipe (5). The tie rod according to claim 1, wherein: 3. Tie rod according to claim 1 or 2, characterized in that the injection tube (5) has a cap opening closed with an elastic sleeve. 4. A pipe (5) arranged adjacent to the injection pipe (5) like the contained strand (4) for pre-embedding the strand in a corrugated duct by injecting cement. 18), characterized in that the injection tube (5) and the pre-filling tube (18) are in communication at their ends with an airtight cap (9).
Tie rod described in. 5. Each corrugated duct (8) comprises a fixing zone (2).
The tie rod according to any one of claims 1 to 4, characterized in that it has a ventilation pipe (18) on the upper part of the tie rod. 6. An end cap for a tie rod according to claims 2 to 4, comprising a casing (10) which is a substantially rotating casing, said casing (10) being one of the ends (11). Is closed and is provided with a plug (12) on the other end, which plug (12) is for supplying corrugated duct (8) and material for pre-embedding the strands in the corrugated duct. An end cap, characterized in that it is pierced by a leading tube (13, 14) adapted to be sealingly connected to the tube (18).