EP1081290A2 - Apparatus and method for producing bearing columns sunk in the ground - Google Patents

Abstract

The device has a ram lance (12), in which a material shaft (15) runs vertically in the working position and about which a cylindrical pipe (21) is displaceably mounted with little play. The pipe can be fixed in several positions along the ram lance length using a coupling device (22). The ram lance is connected to a high frequency vibrator (11) and has a lower advance point (13). The material shaft has an opening and closing mechanism (14) near the lower advance point. An Independent claim is included for a method for using the device.

Description

The invention relates to a device to be used in special civil engineering for the production of sunken support columns such as darning columns or Concrete vibrating columns, with a driving lance, in their working position vertical material shaft runs and around the longitudinally displaceable a pipe is laid with a small clearance, and relates to a method for Manufacture of the support columns with the help of this device, which in principle from the DE-PS 971 834 is known.

Such support pillars are in particular vibrating pillar pillars, mortar pillar pillars and Concrete vibrating columns. These pillars are used to support the load of buildings or of temporary loads, for example on railway bodies and airfields, if under the floor area is initially a non-load-bearing building ground and only in of a certain depth a stable building ground is available. For example in the execution of vibrating plug columns in a columnar created by the vibrator Bottom opening in sections of robust material such as gravel, gravel or Sand installed and compacted by the vibrator and partially into the surrounding Floor areas displaced. This creates a pillar, especially on your Foot has a certain widening. This is introduced for mortar columns Material is still bound or added by adding a cement suspension pre-made mortar such as gravel concrete clogged in the building ground. Finally it is also known to pump concrete into the space created with the help of the ram lance to spend, which creates pile-like columns with high load-bearing capacity. The The ramming lance is shaken with the help of driving into the ground a vertical vibrator on an outer frame on which the ramming lance sits; and the shaking to solidify the material takes place according to the prior art through horizontal vibrations with the help of a around a vertical axis rotating unbalance in the ram.

Older devices, e.g. B. the device described in DE-PS 971 834 for the production of in-situ concrete piles, work on ramming the device with a hammer head (battering ram). The prior art mentioned at the outset is used a pilot tube together with a core tube, the core tube using a striking head on the pre-drive pipe is fixed. Before and during the The core tube, which is always open at the bottom, is arranged so that it is is shorter at its lower end than the pre-drive pipe. During the ramming process it must be completely filled with concrete. Through this complete Filling the core tube with concrete and due to the shorter length a block is formed at the lower end, which is formed from a certain amount of concrete is and serves as a "advancement tip". Not only during the ramming process, during which the core tube must be closed at the top, but also when Pulling out the core tube and the pre-drive tube determines the Pre-drive tube on the core tube. Filling z. B. the concrete is done before driving into the ground and thus for a z. B. 5 m high stuffing column in one Height of 5 m, which requires a corresponding amount of equipment, and conditional due to the necessarily shorter core tube compared to the pre-drive tube, it collects Material underneath the core tube between the advance tube inner walls and tends to be between the outer tube and the core tube during the ramming process To penetrate the inside of the pre-drive pipe.

DE-AS 1 110 092 describes a method and an apparatus for the production Reinforced in-situ concrete foundation piles by means of a pre-drive pipe, which with Help a battering bear is driven in, and one into the ground already introduced pre-drive pipe sunken pouring pipe known, the Pre-drive pipe and the pouring pipe after the concrete has been poured in again synchronously pulled out at the top.

Today's technology does not work with a hammer head, but with vibrating ones Vibrators, namely a vertical vibrator for propulsion and a horizontal vibrator for shaking the filling compound. However, the vibration technology also has its problems. Compacting with the help of horizontal vibration does not result in an optimal one Result, the separate vibrators for vertical and horizontal vibration provide one great effort and also the driving tip is subject to the ram an extremely fast wear, especially when edged material such as grit should be compressed. If concrete columns are manufactured, they are based on the known Procedure the cost is very high. In addition, there is the disadvantage that the Concrete on the outside of the column before setting with the surrounding one does not load-bearing floor matted and due to corners and protrusions like them Known ram lances with horizontal vibrators have bulges, with the Result of increased negative skin friction, including the development of Frictional forces are understood, the column with weight from surrounding unsustainable soil material, unlike in some Scope of load-bearing soil, due to the positive skin friction in this Part of the payload is already supported on the surrounding soil material can be.

Through the invention, the manufacture of the support pillars in several ways optimized. The device according to the invention is characterized in that the around the ram lance along most of the ones to be driven into the ground The ram length of the pipe is shifted longitudinally in several positions with the help a coupling device on the driving lance can be fixed, the driving lance with a Ramm high-frequency vibrator with vertical vibrating force and one has lower propulsion tip, and the material shaft at the lower end in Area of the propulsion tip has an opening and closing mechanism. With this device, the support column can be made by a) that Pipe in a position in which its lower end in the area of the lower end of the Ramming lance is located on the ramming lance, b) the ramming lance with the attached drives the specified pipe into the ground, c) detaches the pipe from the ram, and d) the ram lance retracts in the tube remaining in the ground and a material batch for the support column at the lower end of the ram lance. Depending on the area of application this process is continued by subsequently to step d): e) fix the pipe to the ram lance and a little further pulls above, f) the pipe detaches from the ram lance and the ram lance on the Deposits the top of the dispensed material in the pipe and g) the pipe at the Ramming lance defines and this together with the pipe and the still in it shakes the present portion of the material batch with vertical movement component, and that after step g) steps e) to g) are repeated until the support column reaches the required height; or by using material still flowable concrete used and carried out the writing e) and then Repeat this writing on letter e) until the supporting column reaches the required height reached. The method according to the invention thus includes pulling out the Driving lance together with the pipe attached to it or without the pipe and a subsequent shaking by means of the ram lance with a new tube in the vertical direction, so that you can use the ram lance and the only one vertically acting vibrators move the material in different vertical positions can shake during filling.

The shaking for material compaction is also during pulling up Driving lance possible. It takes a time on the order of, for example 1 minute. In cases where the material is in the pipe and in the top this funnel for the column is sufficient, so this can be done after Ramming can be completed in about a one-minute work step, whereby the ram lance does not have to be brought down again for compaction.

The method according to the invention also allows the stuffing column to be for example, to perform soft layers of height more strongly there by Expansions are made. This is done by compressing the outer tube of the column part lying under the soft layer up to the upper edge pulled up the soft layer and then shaken down new material that forms a belly at this point.

The sunken support columns are ideal even in non-load-bearing floors and are manufactured using a multi-purpose vibrator and at Remaining of the pipe inside the floor during the shaking, even after the material for producing the column has already been introduced into the ground. The ram lance can be moved longitudinally in relation to the pipe and can be before and / or after and / or during the longitudinal displacement the closing and opening mechanism on the material chute is open to let material into the pipe; then can be on the new Longitudinal shift position a new definition of the pipe to the ram lance be carried out by means of the coupling device and then a new shaking process by means of the vertical vibrator.

The support columns manufactured in this way are optimal due to the vertical vibrating force compressed, or is required for a required degree of compression only a moderate vibration force. For ramming and compacting is sufficient a single jogger. The compaction is not done with the tip of the lance but with the lower end of the material enclosed in the tube, so that abrasion at the tip of the lance is considerably reduced. Becomes concrete potted, it binds in the smooth-walled cylindrical cavity that in the ground after the withdrawal of the pipe, the wall thickness of z. B. 10 to 15 mm is formed. The outer surface of the resulting concrete support column is clean and sufficiently smooth to remove the negative skin friction of the surrounding Avoid layer of soil. This is especially true if already on one below created compacted material accumulation or concrete filling that a column base forms, by opening the system of the device and placing a precast concrete pile, the placed on this previously created column base and if necessary connected to it, a column with a completely smooth surface is embedded in the relevant soil layer.

Since the system can be opened at any time when placing the support columns, to insert the desired material into the pipe and closed again can be used, the device according to the invention can be used very universally.

The detachable coupling between the ram lance and the pipe can can be produced in various ways. A form-fitting coupling comes into question, For example, by moving inwards at the top of the tube Projections that are in complementary recesses such as grooves or troughs on the Intervene on the outside of the ram lance. In the interest of simplified production and a smooth lance outer surface is a frictional attack on the cylindrical lance outer surface preferred. For simpler versions this can be done by a manually operated screw spindle, however, because also the nearby vibrator is generally a hydraulically operated vibrator is preferred, an attack of investment jaws, by the top of the tube Seated hydraulic presses, for example, in the form of Hydraulic cylinder-piston units are operated. Of these units is enough basically one, the lance is then on the other side to the inside of the pipe pressed; however, two or three are preferably symmetrical to the tube axis arranged units used. According to another alternative comes too an electromagnetic coupling that is directly coupled to the material of the Component works or works via system jaws, into question.

Fig. 1

eine teilweise geschnittene Darstellung einer Anlage zur Erstellung von versenkten Tragsäulen in nicht tragfähigem Boden;

Fig.n 2 bis 4

in vergrößertem Maßstab Schnittdarstellungen der wesentlichen Teile der Anlage in verschiedenen Arbeitsphasen der Erstellung der Tragsäulen;

Fig.n 5 und 6

Darstellungen vergleichbar Fig. 4 bei abgewandelten Verfahrensdurchführungen.

Further details, advantages and developments of the invention result from the following description of preferred exemplary embodiments with reference to the drawing. Show it:

Fig. 1

a partially sectioned representation of a system for creating sunken support columns in unsustainable soil;

Fig.n 2 to 4

on an enlarged scale sectional views of the essential parts of the system in various phases of the creation of the support columns;

Fig.n 5 and 6

Representations comparable to FIG. 4 with modified method implementations.

1, a building, a roadway or the like be built on non-load-bearing floor 1 by horizontal dot-dash hatching is indicated. There is a layer only at a certain depth load-bearing floor 2, indicated in Fig. 1 by rough dot hatching is. To derive the weight down to the stable floor 2 is therefore as usual, set up a field of support or support columns, for example darning columns from gravel, split, gravel, sand or lime or from concrete vibrating columns, which in the Ground to be poured. In Fig. 1 a finished support column 3 is shown, one the second one is under construction. For this purpose, a crawler track 4 with a tower 5 has been started up and installed.

On the tower 5 sits a vertically movable working head 6, which has a Vibrator 11 with a vertical vibrating motion a downward ram 12 leads. The ram lance consists of a circular cylindrical tubular elongated Housing of, for example, 30 or 35 cm in diameter, in its There are various installations inside. At the bottom it has Ram lance a propulsion tip 13, but which also has a locking device an opening and closing mechanism 14 forms. This consists in the shown Example from a on a shaft that is limited in the lance 12 Wide is guided, seated conical valve body, which alone open and close by weight and external pressure forces. An alternative would be a mechanism of sector locking slats. One in the ram lance 12 in the longitudinal direction of the material shaft 15 (Fig. 6) for trickle materials Loadable via a loading device 16 and via the through the tunneling tip 13 formed closure can be discharged in batches below. In the case of creation In a concrete vibrating column, the loading device consists of one Concrete pump coming flexible line and one in the ram lance 12th extending conduit 18 for concrete and cement suspension. The vibrator 11 engages on the ram lance 12 via a tab 19.

The ram lance 12 is cut within one in the drawings shown circular cylindrical tube 21, which at its upper end has a coupling device 22 for reversible fixing on the ram lance 12. The lance 12 slides on the inner tube surface with a sufficiently narrow gap that penetration of foreign material into the gap, in particular from the material that later to form the support column is largely avoided. Maybe outside There is a wiper ring (not shown) on the lance or inside the pipe be similar to an oil scraper ring in common piston-cylinder units. The pipe is chamfered on its lower edge and this chamfer together with the Driving tip 13 of the ram lance 12 in the position according to Fig.n 1 and 2 a common conical surface. In the described embodiment, there is Coupling device consisting of two opposing hydraulically loaded pistons 23, the coupling by pressing on the outer surface of the ram lance 12th cause. The presentation assumes a frictional contact, but can for example, by means of grooves on both sides, also a positive contact be provided.

2, the ram lance is - as far as in the prior art - With the help of the vibrating in the vertical direction, shown only schematically in Fig. 2 Vibrator 11 through the vertical vibration actuation in the range of the load-bearing Rammed floor 2. Here, however, the pipe 21 is rammed in, that sits firmly on the ram lance 12 with the aid of the coupling device 22 and this surrounds in the area of its lower end. The driving depth can depend on go from the nature of the load-bearing floor 2 to its top (Fig. 1), or the ram lance 12 is a little further into the load-bearing soil 2 rammed (Fig. 2) so that the resulting support column 3 is anchored in this.

After this ramming process, the coupling device 22 is released and the Ram lance 12 withdrawn upwards, the tube 21 reached in the Position in the floor remains. Now, as shown in Fig. 3, the opening and Closing mechanism 14 and over the material shaft 15 in the ram 12 material 24, which is to form the support column 3, is drained down where it is the pipe 21 fills in whole or in part and settles down on or in the load-bearing floor 2 discontinues. Fig. 3 shows the filling of the entire pipe length at once, here can but can also be done in smaller steps. In the figure is the material 24 shown as a coarse-grained trickle, but here all come for supporting columns suitable materials.

Then - still with the coupling device 22 released - the the opening and closing mechanism 14 given closure closed be what in the mechanism shown only by lowering the ram 12 takes place on the material 24, or no more material is added; Then it will be the coupling mechanism activates and together with the ram lance the pipe Pulled a bit out of the ground and in an elevated position back on the ram lance 12 set. The column material 24 initially gives way a little at the bottom laterally into the non-load-bearing floor 1 or the load-bearing floor 2. To the renewed coupling of the tube 21 to the ram lance 12 with the aid of the coupling device 22 begins again according to FIG. 4, the vibrator 11 to do that to release released material 24. The tube 21 makes the vibrations with the ram lance 12 with. The level that acts as the actual hammer level is not the propulsion tip 13, but a plane 26, which is the lower end plane of the tube 21. The abrasion of the driving tip 13 or the lamellae 14 is therefore limited. The material 24 below the tube there forms a wide column base 27, above which a column shaft is initially in the tube 21 28 is formed. The procedure with lifting the ram lance 12, subsequent deliveries of material 24, tightening the tube 21 and shaking can now in steps up be repeated to the top of the bottom 1.

Fig. 5 illustrates another implementation in which after the first Introducing and compacting material does not add more material, but instead a precast concrete column 29 is introduced. For this purpose, the ram lance 12 from the Tube 21 pulled out and then inserted into this column 29, which on the from the first material 24 existing column base 27 is provided. This column base 27, which carries the precast concrete column 29, can itself be made of concrete or can be made from one of the other supporting materials such as gravel etc. consist.

If the concrete column is to be made of in-situ concrete, then you can already do so compressed column base in the tube 21, a reinforcement 32 can be set, which then is embedded in the poured concrete. This is shown in FIG. 6.

Claims (10)

Device for producing support columns (3) sunk into the ground, such as darning columns or concrete vibrating columns, with a ram lance (12) in which a material shaft (15) runs in its vertical longitudinal direction in the working position and around which a tube (21) can be moved with little play is characterized in that the pipe (21) placed around the ram lance (12) along the majority of the ram lance length to be driven into the ground is displaceable in several positions with the aid of a coupling device (22) on the ram lance, the ram lance (12) is connected to a ramming high-frequency vibrator (11) with vertical vibrating force and has a lower propulsion tip (13), and the material shaft (15) has an opening and closing mechanism (14) at the lower end in the region of the propulsion tip. Apparatus according to claim 1, the coupling device (22) one in one of the Elements - ram lance (12) or tube (21) - seated, at the other of these Elements frictionally engaging pressure device (23). Device according to claim 2, characterized in that the pressing device from hydraulic presses arranged symmetrically with respect to the pipe axis consists. Method for producing support columns (3) sunk in the ground with the aid of the device according to one of Claims 1 to 3, characterized in that a) fixes the tube (21) on the ram lance (12) in a position in which its lower end is at the lower end of the ram lance, b) drives the ram into the ground (1) with the pipe attached to it, c) the pipe detaches from the ram, and d) the ram lance retracts in the tube remaining in the ground and releases a material batch (24) for the support column at the lower end of the ram lance. A method according to claim 4, characterized in that after step d): e) fixes the pipe (21) on the ram lance (12) and pulls it up a little, f) the pipe detaches from the driving lance and the driving lance settles in the pipe on the upper side of the dispensed material (24) and g) fixes the pipe to the ram lance and shakes it together with the pipe and the part of the material batch with the vertical movement component still in place. A method according to claim 5, characterized in that subsequently Repeat steps e) to g) on step g) until the support column meets the required requirements Height reached. A method according to claim 4, characterized in that the material still flowable concrete is used and before the concrete sets Performs step e) according to claim 5. A method according to claim 7, characterized in that in the tube before dispensing the concrete after step d) there are reinforcements, which are then from Concrete are covered. A method according to claim 7 or 8, characterized in that subsequently Repeat steps d) and e) at step e) until the support column (3) reached the required amount. Method according to one of claims 5 to 9, characterized in that one after the first or repeated execution of the step e) or g) on the surface of the material delivered (24) a precast concrete column (29), which is removed through the pipe (21) the ram lance (12) leads down.

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