DE599931C - Method and device for the production of place posts with bulges or thickened shafts - Google Patents

Description

Method and device for the production of in-situ piles with bulges or shaft thickenings In previously known processes for the production of The jacking pipe is piles in place by means of ramming at the lower end of the pipe Gravel, gravel, sand, concrete mix or the like introduced into the pipe into the ground lowered. During this process, a plug forms at the bottom of the pipe, which is removed or knocked out downwards after the pipe has been lowered. The site pile is then produced by placing concrete in the pipe and tamping or ramming the concrete while pulling up the pipe.

This method has the disadvantage that a compaction of the soil when lowering the pipe only takes place through the ground displaced by the pipe, while an intended further compaction by means of larger amounts of concrete only brought about when the pipe is pulled up by the concrete protruding over the pipe foot can be.

The difficulties that arise when subsequently compressing the Enter the ground are known. In this method of soil compaction, the Consumption of concrete hard to miss, and there is a risk of pulling it up of the pipe, all of the concrete still present in the pipe is tamped out, if new concrete is not poured into the pipe beforehand. In such cases the dangerous pile constrictions or even pile breaks occur.

In the case of the known `` experienced '' the intended iron reinforcement is presented lowered into the '\ rort driving pipe before concreting. However, experience has shown that then this iron reinforcement becomes a strong obstacle when ramming the concrete, by the production of the so-called pile bulges or a "purulent soil compaction is difficult or imperfect to achieve. The iron reinforcement is also used bent and shifted so that there is no longer any guarantee. that they are finished Stake in the right place.

The disadvantages of the known methods outlined by the Invention avoided by compacting the soil by means of concrete or the bead and shaft thickening of the concrete pile already when the Propulsion pipe are generated.

The invention consists in that for the purpose of soil compaction and formation the bulges more or less into the propulsion pipe during its lowering the movement is braked or repeatedly stopped and the soil compaction and bulging of the concrete required in each case by means of the tamper is stamped out of the V ortreibrohr, and that finally when pulling up of the jacking pipe, only the space it occupies is concreted out.

The invention also consists in an expedient embodiment of the jacking pipes and rams required for the process.

In Figs. I to 3 embodiments of the invention are shown. Fig. I shows the vertical section through a normal jacking pipe a, its clearances Cross-section is practically the same size from top to bottom, while Fig. A is a conical one Shows training of the lower pipe part. Furthermore, Fig. 3 shows with regard to the conical Formation of the wall surface of the tube a modified form in which here the outer Diameter of the pipe from top to bottom remains approximately constant while he as in Fig. 2 increases in the lower part of the pipe.

For the purpose of lowering the propulsion pipe according to Fig Pipe placed on the ground and provided with a device through which the Ramming the penetration of the pipe into the ground is slowed down or the pipe may be. entirely is being held. This device can, for example, consist of two screws against each other pressed wooden beams exist, which enclose the pipe and on the ground rest. The braking effect can be increased by tightening the screws. On that an amount of concrete corresponding to the manufacturing process of the concrete pile is used in <las tube brought by means of a ltainnibear b, the diameter of which is in a certain ratio to the diameter of the jacking pipe is rammed. The frictional pressure that occurs between the concrete and the inner pipe wall depends on it the pipe cross-section, the shape, weight and height of fall of the ram, the im The amount of concrete in the pipe, its composition, the flexibility of the soil as well as other causes given by the local conditions. Because of under these circumstances, the amount of concrete poured into the pipe is calculated in such a way that that when ramming the concrete and braking the pipe at the same time a certain Amount of concrete on the lower pipe swells outwards or is pressed outwards, so that during the ramming between the outer pipe wall and the ground a certain Concrete layer c arrives. depending on the type of soil and the operating facilities selected, The concrete layer is one of the elements that include the jacking pipe and the pile-driving device be stronger or weaker on the outer circumference of the pipe. With soft soil layers this concrete layer z. B. take the form of a larger bead d. By the described operation thus occurs the intended .Verdichtung des Soil already during the lowering of the pipe, and when pulling it up later of the jacking pipe only needs the concrete cross-section displaced by the pipe out - to be rammed. Here there is the greatest guarantee that this Wise made place post that dangerous constrictions cannot occur.

During the pile-driving work, the braking of the pipe can be increased so much that the pipe is brought to a complete standstill. That way, with Safety achieved that, depending on the strength of the braking exerted on the pipe Concrete is pressed out at the side of the pipe and as a result of the artificially slowed down As the pipe slides down, the outer concrete layer c forms or bulges d arise. In contrast to the known processes, the process becomes more present Invention beads d formed or an increased soil compaction achieved without constrictions of any kind can arise. Even if from any Reason the timely refilling of concrete into the pipe interior has not been carried out, in this way, no disadvantages can occur for the pile that will be completed later. Here in is an extremely great advantage of the process.

To make it easier to push out the concrete to the side at the lower end of the pipe, it may be useful to put the propulsion pipe in the lower part, for. B. according to Fig. A or 3. to be conical. This conical design allows for the work process advantageous friction conditions can be achieved, in particular 'with regard to the Friction between concrete and the inner pipe wall as well as between concrete and ram. Therefore, larger amounts of concrete can possibly advantageously get into the pipe be introduced without thereby reducing the friction between the inner pipe wall and Concrete is increased. For the process of soil compaction with concrete then exist particularly favorable conditions.

In order to be partly independent of the frictional forces by which the effects of the Raminbärs are transferred to the propulsion pipe when lowering the propulsion pipe, projections e (Fig. D.) On the lower part of the propulsion pipe and also projections f - (Fig .4) are used on the ram .. On - the concrete layer located between the projections e and f then have a partially direct effect due to the projections f. They are then partially transferred from the aforementioned concrete layer to the projections e. Depending on the choice of the size of the relevant support surface of the projections e and f, it can be achieved that a certain amount of concrete is constantly rammed through the open pipe opening remaining at projection e, which then creates a concrete layer c on the outer pipe circumference or concrete beads. d generated.

In this process, the projections e and f do not touch, so that the concrete located between the projections e and f through the clear pipe opening at the projection e can constantly pass.

It is of course not necessary for the projections e and f to be provided at the same time; only projections e or f can also be used alone.

The projection e can optionally also have a different shape c (according to Fig. 5). A particular advantage of the invention is that the Piles can be provided with iron reinforcement in a simple manner without that this makes soil compaction difficult. After the jacking pipe is lowered and thus the increased soil compaction due to the concrete beads etc. has already been done, iron reinforcement is required before the jacking pipe is pulled up or a reinforcement frame lowered into the pipe. As it is while pulling up of the driving pipe is no longer a matter of completing the soil, but only proper concreting of the pile cross-section displaced by the jacking pipe, so there is no more bending or shattering of the iron framework, all the more so the remaining part of the pile shaft is finally simply poured with cast concrete can be.

Claims (5)

PATENT CLAIM: i. Process for the manufacture of in-place piles with Bulges or thickened shafts, in which a propulsion tube open at the bottom by means of Ramming is driven down onto a quantity of concrete provided in its lower end, characterized in that the pipe for the purpose of soil compaction and formation of the beads more or less braked or repeated in movement while it is being brought down is stopped and the respective required for soil compaction and bulge formation Concrete is tamped out of the jacking pipe by means of the tamper, and that finally When pulling up the V ortreibrohres only the space occupied by it concreted will. 2. propulsion pipe for carrying out the method according to claim i, characterized in that that it is flared at the lower end. 3. Propulsion pipe for the execution of the Method according to claim i, characterized in that it is in the vicinity of the lower Has one or more internal approaches (e, e ') at the end. 4. Propulsion pipe according to claim 3, characterized in that the annular extension (e ') is downward gradually merges into the propulsion pipe. 5. Ram to carry out the procedure according to claim i, characterized in that it is provided with annular projections (f) is.