CH648074A5

CH648074A5 - Method of constructing a cast-in-place pile

Info

Publication number: CH648074A5
Application number: CH510680A
Authority: CH
Inventors: Franz Leutert
Original assignee: Fietz & Leuthold Ag
Priority date: 1980-07-02
Filing date: 1980-07-02
Publication date: 1985-02-28

Abstract

To construct a cast-in-place pile, a pipe (1) closed at the bottom is connected to a vibrator (4) in a tension-proof and compression-proof manner and is vibrated into the ground by the same. Then concrete is put into the pipe and the pipe is then vibrated partly upwards, in the course of which the pipe opens at the bottom and the concrete comes out. Then the pipe is vibrated downwards again in order to produce a widened portion (7) at the pile base. Then concrete is poured into the pipe again and the same is vibrated out of the ground. The use of a vibrator not only permits especially quick lowering and withdrawal of the pipe but also brings about advantageous compaction of the ground through the vibrations of the pipe. <IMAGE>

Description

**WARNUNG** Anfang DESC Feld konnte Ende CLMS uberlappen **. ** WARNING ** beginning of DESC field could overlap end of CLMS **.

PATENTANSPRÜCHE 1. Verfahren zur Erstellung eines Ortbetonpfahls, insbesondere in losem Boden, dadurch gekennzeichnet, dass man ein unten mit einem klappbaren Abschluss verschlossenes Rohr mittels eines am oberen Rohrende druck- und zugfest angebrachten Vibrators zuerst niederbringt, dann mindestens einmal Beton in das Rohr einbringt, das Rohr mittels des Vibrators hochvibriert um Beton bei offenem Abschluss nach unten austreten zu lassen, worauf man das Rohr bei sich schliessendem Abschluss wieder nach unten vibriert, um den darunter befindlichen Beton zu verdichten und zur Pfahlfussverbreiterung, und dass man schliesslich das mit Beton gefüllte Rohr aus dem Boden hochvibriert. PATENT CLAIMS 1. Method for creating an in-situ concrete pile, in particular in loose soil, characterized in that one first brings down a pipe closed at the bottom with a hinged closure by means of a vibrator attached to the upper pipe end in a pressure-resistant and tensile manner, then at least once concrete is introduced into the pipe, which The pipe is vibrated upwards by means of the vibrator in order to allow concrete to emerge downwards when the closure is open, whereupon the pipe is vibrated downwards when the closure is closed in order to compact the concrete underneath and to widen the pile foot, and finally to remove the concrete-filled pipe vibrated up the floor.

2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass man nach dem Einvibrieren des Rohrs auf volle Tiefe 3-5 m hoch Beton einfüllt, dann das Rohr um 3 m hochvibriert und dann wieder abwärts vibriert. 2. The method according to claim 1, characterized in that after vibrating the pipe is filled to the full depth of 3-5 m high concrete, then vibrating the pipe by 3 m and then vibrating downwards again.

Die folgende Erfindung betrifft ein Verfahren zur Erstellung eines Ortbetonpfahls, insbesondere in losem Boden. Es ist bekannt, zur Erstellung von Ortbetonpfählen am unteren Ende verschlossene Rohre einzurammen und sie anschliessend nach dem Einfüllen von Beton zurückzuziehen. Entweder wird dabei auf das obere Rohrende gerammt oder aber es wird mit einem Fallgewicht auf den trockenen Betonspiegel im Rohr geschlagen, um den Beton zusammen mit dem Rohr einzurammen. Am unteren Rohrende ist entweder eine verlorene Betonspitze oder Stahlspitze angebracht, während in anderen Fällen dank dem dichten trockenen Beton das Rohr offen bleibt. Ausserdem ist es bekannt am unteren Rohrende eine Klappe anzubringen, die beim Einrammen des Rohrs geschlossen bleibt und beim Zurückziehen des Rohrs sich öffnet und den Beton nach unten austreten lässt. The following invention relates to a method for creating an in-situ concrete pile, in particular in loose soil. It is known to ram closed pipes at the lower end to create in-situ concrete piles and then to pull them back after the concrete has been poured in. Either it is rammed onto the upper end of the pipe or it is struck with a drop weight on the dry concrete level in the pipe in order to ram the concrete together with the pipe. Either a lost concrete tip or steel tip is attached to the lower pipe end, while in other cases the pipe remains open thanks to the dense dry concrete. In addition, it is known to attach a flap to the lower end of the pipe, which remains closed when the pipe is driven in and opens when the pipe is pulled back, allowing the concrete to emerge downwards.

Diese bekannten Verfahren sind alle mit gewissen Nachteilen verbunden. Die Geschwindigkeit, mit welcher das Rohr in den Boden eingetrieben werden kann, ist in allen Fällen beschränkt. Das Einrammen des Rohrs ist mit erheblichem Lärm verbunden, besonders wenn die Rammvorrichtung auf das obere Rohrende wirkt. These known methods are all associated with certain disadvantages. The speed at which the pipe can be driven into the ground is limited in all cases. The ramming of the pipe is associated with considerable noise, especially when the ramming device acts on the upper end of the pipe.

Es ist das Ziel vorliegender Erfindung, diese Nachteile zu vermeiden und zudem überraschende Vorteile zu erzielen. The aim of the present invention is to avoid these disadvantages and also to achieve surprising advantages.

Das erfindungsgemässe Verfahren ist dadurch gekennzeichnet, dass man ein unten mit einem klappbaren Abschluss verschlossenes Rohr mittels eines am oberen Rohrende druck- und zugfest angebrachten Vibrators zuerst niederbringt, dann mindestens einmal Beton in das Rohr einbringt, das Rohr mittels des Vibrators hochvibriert um Beton bei offenem Abschluss nach unten austreten zu lassen, worauf man das Rohr bei geschlossenem Abschluss wieder nach unten vibriert um den darunter befindlichen Beton zu verdichten und zur Pfahlfussverbreiterung, und dass man schliesslich das mit Beton gefüllte Rohr aus dem Boden hochvibriert. Es hat sich gezeigt, dass ein Stahlrohr mittels eines Vibrators wesentlich rascher und geräuschärmer abgesenkt werden kann als mittels der oben erwähnten bekannten Rammverfahren.Zudem ergibt sich trotz der nur in Richtung der Rohrachse wirkenden Vibrationen eine überraschend intensive Verdichtung des das Rohr umgebenden Bodens, was besonders bei losem, kiesigem, rollfähigem Boden von besonderer Bedeutung ist. Es ist zwar an sich bekannt, eine Bodenverdichtung durch Vibrieren zu erzielen, aber es konnte nicht ohne weiteres erwartet werden, dass auch beim Einvibrieren eines Rohrs in den Boden eine Verdichtung desselben erzielt wird, welche sich nachträglich in der Haftfähigkeit des erstellten Ortbetonpfahls günstig auswirkt. The method according to the invention is characterized in that a pipe which is closed at the bottom with a hinged closure is first brought down by means of a vibrator which is attached to the upper pipe end in a pressure-resistant and tensile manner, then concrete is introduced into the pipe at least once, the pipe vibrates upwards by means of the vibrator around concrete when open Let the bottom exit, whereupon the tube is vibrated down again when the end is closed to compact the concrete underneath and to widen the pile foot, and finally vibrate the tube filled with concrete from the ground. It has been shown that a steel tube can be lowered much more quickly and quietly by means of a vibrator than by means of the known ramming methods mentioned above. In addition, despite the vibrations that only act in the direction of the tube axis, there is a surprisingly intensive compaction of the soil surrounding the tube, which is particularly important with loose, gravelly, rollable soil is of particular importance. Although it is known per se to achieve soil compaction by vibrating, it could not be expected that compaction of a pipe into the ground would result in compaction, which would have a positive effect on the adhesiveness of the in-situ concrete pile created.

Während bei den oben erwähnten bekannten Verfahren beim Erstellen des Ortbetonpfahls ein Vibrator in den aus dem Rohr austretenden Beton eingebracht werden musste, erübrigt sich diese Massnahme beim erfindungsgemässen Vorgehen auch, indem das vibrierende Rohr in allen Phasen der Erstellung des Pfahls einen eingehängten Vibrator ersetzt. While a vibrator had to be introduced into the concrete emerging from the pipe when creating the in-situ concrete pile in the known methods mentioned above, this measure is also unnecessary in the procedure according to the invention in that the vibrating pipe replaces a suspended vibrator in all phases of the construction of the pile.

Die Erfindung wird nun anhand der Zeichnung näher erläutert, welche in den Figuren 1 bis 6 verschiedene Stadien des Verfahrens darstellt. The invention will now be explained in more detail with reference to the drawing, which shows different stages of the method in FIGS. 1 to 6.

Gemäss Fig. list ein Stahlrohr 1 bereits auf die gewünschte Tiefe in den Boden einvibriert worden. Am unteren Ende des Rohres befindet sich ein Deckel 2, der sich um ein Scharnier 3 nach unten schwenken lässt. Am oberen Ende des Rohres 1 ist ein Vibrator 4 mittels hydraulischer Pressen druck- und zugfest angebracht. Wie durch einen Seilzug 5 angedeutet, hängt dieser Vibrator an einem geeigneten, nicht dargestellten, Hebezeug. Es kann auch ein ebenfalls nicht dargestellter Mäkler vorhanden sein, an welchem der Vibrator 4 und/oder das Rohr 1 in vertikaler Richtung geführt sind. In allen Figuren ist angedeutet, dass das Rohr drei Schichten des Bodens durchsetzt, nämlich beispielsweise eine obere lose Schicht, eine mittlere undurchlässige Schicht und eine untere tragende Schicht. Die eigentliche Verankerung des Pfahls soll in der tragenden Schicht erfolgen. According to FIG. 1, a steel pipe 1 has already been vibrated into the ground to the desired depth. At the lower end of the tube there is a cover 2 which can be pivoted downwards by a hinge 3. At the upper end of the tube 1, a vibrator 4 is attached pressure and tensile resistant by means of hydraulic presses. As indicated by a cable 5, this vibrator hangs on a suitable lifting device, not shown. There may also be a leader, also not shown, on which the vibrator 4 and / or the pipe 1 are guided in the vertical direction. In all figures it is indicated that the pipe passes through three layers of the floor, namely for example an upper loose layer, a middle impermeable layer and a lower load-bearing layer. The actual anchoring of the pile should take place in the load-bearing layer.

Im Stadium gemäss Fig. 2 ist der Vibrator vom Rohr 1 entkuppelt und angehoben und es ist aus dieser Figur ersichtlich, dass in das oben offene Rohr 1 Beton 6 bis auf eine gewisse Höhe, beispielsweise 3-5 m über dem Deckel 2, eingefüllt worden ist. Ist dieses Stadium erreicht, wird nun der in Stirnansicht dargestellte Vibrator 4 wieder mit dem Rohr 1 gekuppelt und derart eingeschaltet, dass das Rohr 1 nach oben vibriert wird. Dabei öffnet sich der Deckel 2 infolge Eigengewicht sowie einseitiger Aufhängung und unter dem Druck des eingefüllten Betons 6 und lässt diesen Beton austreten. Es wird in dieser Weise das Stadium nach Fig. 3 erreicht, d.h. das Rohr list um eine gewisse Strecke angehoben, beispielsweise um 3 m und der darin befindliche Beton ist weitgehend durch das unten offene Rohr in das Bohrloch unter dem Rohr ausgetreten.Hierauf wird der Vibrator 4 umgestellt, um das Rohr 1 erneut nach unten zu vibrieren. Infolge des vorderen angeschrägten Endes, wird der Deckel 2 dabei geschlossen, derart dass der unter dem Rohr befindliche Beton nicht wieder in das Rohr eintreten kann, sondern verdichtet und zu einer Pfahlfussverbreiterung oder Zwiebel 7, gemäss Fig. 4 erweitert wird. Wie ebenfalls Fig. 4 darstellt, wird nun nach Erreichen der unteren Stellung des Rohres 1, bzw. nach genügender Verdrängung und Verdichtung des Betons zur Zwiebel 7, wiederum Beton in das Rohr 1 eingefüllt und zwar ungefähr bis auf Bodenhöhe. In der Folge wird das Rohr gemäss Fig. 5 nach oben vibriert, wobei der darin befindliche Beton austritt und im Bohrloch den Ortbetonpfahl 8 zurücklässt, der in Fig. 6 nach seiner Fertigstellung dargestellt ist. In the stage according to FIG. 2, the vibrator is uncoupled from the pipe 1 and raised and it can be seen from this figure that concrete 6 has been poured into the pipe 1 open at the top to a certain height, for example 3-5 m above the cover 2 is. If this stage is reached, the vibrator 4 shown in the end view is now coupled again to the pipe 1 and switched on in such a way that the pipe 1 is vibrated upwards. The lid 2 opens due to its own weight and one-sided suspension and under the pressure of the filled concrete 6 and allows this concrete to emerge. The stage of Fig. 3 is reached in this way, i.e. the pipe is lifted by a certain distance, for example by 3 m, and the concrete inside it has largely escaped through the pipe open at the bottom into the borehole below the pipe Vibrate tube 1 down again. As a result of the front bevelled end, the cover 2 is closed in such a way that the concrete located under the pipe cannot enter the pipe again, but is compacted and expanded to a pile foot widening or bulb 7, as shown in FIG. 4. As also shown in FIG. 4, after reaching the lower position of the tube 1, or after sufficient displacement and compaction of the concrete to form the onion 7, concrete is again poured into the tube 1, approximately to the level of the floor. 5, the pipe is vibrated upwards, the concrete therein exiting and leaving the in-situ concrete pile 8 in the borehole, which is shown in FIG. 6 after its completion.

Wie bereits erwähnt, wird nicht nur während des ganzen Erstellungsprozesses der Beton durch die Vibration des Rohres laufend verdichtet, sondern auch der das Rohr bzw. As mentioned earlier, it will not only be throughout Creation process of the concrete by the vibration of the Tube continuously compressed, but also the tube or

den Pfahl umgebende Boden wird durch die Vibration erheblich verdichtet, wodurch die Belastbarkeit des Pfahls verbessert wird. The floor surrounding the pile is considerably compacted by the vibration, which improves the load-bearing capacity of the pile.

Es ist oben angenommen worden, das Rohr werde zur Bildung einer Pfahlfussverbreiterung einmal zurückgezogen und wieder vorgetrieben (Fig. 3 und 4). Es ist aber möglich, diesen Vorgang zu wiederholen, um entweder die eine Verbreiterung zu vergrössern oder zu erhöhen oder aber um an verschiedenen geeigneten Stellen erweiterte Pfahlteile zu erstellen. It was assumed above that the tube was pulled back once to form a pile foot widening and pushed again (FIGS. 3 and 4). However, it is possible to repeat this process either to increase or increase the widening or to create expanded pile parts at various suitable locations.

Im Stadium gemäss Fig. 3 kann auch ein Armierungskorb in das Rohr eingebracht werden, bevor gemäss Fig. 4 Beton nachgefüllt wird. In the stage according to FIG. 3, a reinforcement basket can also be introduced into the pipe before concrete is refilled according to FIG. 4.

Bei der Erstellung langer Pfähle können mehrere Rohrab When creating long piles, several pipes can be

schnitte nacheinander abgesenkt werden, wobei jeweils nach dem Einvibrieren eines Rohrabschnitts der Vibrator von diesem gelöst, das obere Ende dieses Rohrabschnitts mit dem nächsten Rohrabschnitt zug-, druck- sowie vibrationsfest verbunden und dann der Vibrator zum weiteren Einvibrieren der verbundenen Rohrabschnitte mit dem oberen Ende des letzten angefügten Rohrabschnitts verbunden wird. cuts are successively lowered, each time after vibrating a pipe section, the vibrator is released from it, the upper end of this pipe section is connected to the next pipe section in a tensile, pressure-resistant and vibration-proof manner, and then the vibrator for further vibration of the connected pipe sections with the upper end of the pipe section last attached pipe section is connected.

Claims

PATENT CLAIMS

1. Method for creating an in-situ concrete pile, in particular in loose soil, characterized in that one first brings down a pipe closed at the bottom with a hinged closure by means of a vibrator attached to the upper pipe end in a pressure-resistant and tensile manner, then at least once concrete is introduced into the pipe, which The pipe is vibrated upwards by means of the vibrator in order to allow concrete to emerge downwards when the closure is open, whereupon the pipe is vibrated downwards when the closure is closed in order to compact the concrete underneath and to widen the pile foot, and finally to remove the concrete-filled pipe vibrated up the floor.

2. The method according to claim 1, characterized in that after vibrating the pipe is filled to the full depth of 3-5 m high concrete, then vibrating the pipe by 3 m and then vibrating downwards again.

The following invention relates to a method for creating an in-situ concrete pile, in particular in loose soil. It is known to ram closed pipes at the lower end to create in-situ concrete piles and then to pull them back after the concrete has been poured in. Either it is rammed onto the upper end of the pipe or it is struck with a drop weight on the dry concrete level in the pipe in order to ram the concrete together with the pipe. Either a lost concrete tip or steel tip is attached to the lower pipe end, while in other cases the pipe remains open thanks to the dense dry concrete. In addition, it is known to attach a flap to the lower end of the pipe, which remains closed when the pipe is driven in and opens when the pipe is pulled back, allowing the concrete to emerge downwards.

These known methods are all associated with certain disadvantages. The speed at which the pipe can be driven into the ground is limited in all cases. The ramming of the pipe is associated with considerable noise, especially when the ramming device acts on the upper end of the pipe.

The aim of the present invention is to avoid these disadvantages and also to achieve surprising advantages.

The method according to the invention is characterized in that a pipe which is closed at the bottom with a hinged closure is first brought down by means of a vibrator which is attached to the upper pipe end in a pressure-resistant and tensile manner, then concrete is introduced into the pipe at least once, the pipe vibrates upwards by means of the vibrator around concrete when open Let the bottom exit, whereupon the tube is vibrated down again when the end is closed to compact the concrete underneath and to widen the pile foot, and finally vibrate the tube filled with concrete from the ground. It has been shown that a steel tube can be lowered much more quickly and quietly by means of a vibrator than by means of the known ramming methods mentioned above. In addition, despite the vibrations that only act in the direction of the tube axis, there is a surprisingly intensive compaction of the soil surrounding the tube, which is particularly important with loose, gravelly, rollable soil is of particular importance. Although it is known per se to achieve soil compaction by vibrating, it could not be expected that compaction of a pipe into the ground would result in compaction, which would have a positive effect on the adhesiveness of the in-situ concrete pile created.

While a vibrator had to be introduced into the concrete emerging from the pipe when creating the in-situ concrete pile in the known methods mentioned above, this measure is also unnecessary in the procedure according to the invention in that the vibrating pipe replaces a suspended vibrator in all phases of the construction of the pile.

The invention will now be explained in more detail with reference to the drawing, which shows different stages of the method in FIGS. 1 to 6.

According to FIG. 1, a steel pipe 1 has already been vibrated into the ground to the desired depth. At the lower end of the tube there is a cover 2 which can be pivoted downwards by a hinge 3. At the upper end of the tube 1, a vibrator 4 is attached pressure and tensile resistant by means of hydraulic presses. As indicated by a cable 5, this vibrator hangs on a suitable lifting device, not shown. There may also be a leader, also not shown, on which the vibrator 4 and / or the pipe 1 are guided in the vertical direction. In all figures it is indicated that the pipe passes through three layers of the floor, namely for example an upper loose layer, a middle impermeable layer and a lower load-bearing layer. The actual anchoring of the pile should take place in the load-bearing layer.

In the stage according to FIG. 2, the vibrator is uncoupled from the pipe 1 and raised and it can be seen from this figure that concrete 6 has been poured into the pipe 1 open at the top to a certain height, for example 3-5 m above the cover 2 is. If this stage is reached, the vibrator 4 shown in the end view is now coupled again to the pipe 1 and switched on in such a way that the pipe 1 is vibrated upwards. The lid 2 opens due to its own weight and one-sided suspension and under the pressure of the filled concrete 6 and allows this concrete to emerge. The stage of Fig. 3 is reached in this way, i.e. the pipe is lifted by a certain distance, for example by 3 m, and the concrete inside it has largely escaped through the pipe open at the bottom into the borehole below the pipe Vibrate tube 1 down again. As a result of the front bevelled end, the cover 2 is closed in such a way that the concrete located under the pipe cannot enter the pipe again, but is compacted and expanded to a pile foot widening or bulb 7, as shown in FIG. 4. As also shown in FIG. 4, after reaching the lower position of the tube 1, or after sufficient displacement and compaction of the concrete to form the onion 7, concrete is again poured into the tube 1, approximately to the level of the floor. 5, the pipe is vibrated upwards, the concrete therein exiting and leaving the in-situ concrete pile 8 in the borehole, which is shown in FIG. 6 after its completion.

As mentioned earlier, it will not only be throughout Creation process of the concrete by the vibration of the Tube continuously compressed, but also the tube or

The floor surrounding the pile is considerably compacted by the vibration, which improves the load-bearing capacity of the pile.

It was assumed above that the tube was pulled back once to form a pile foot widening and pushed again (FIGS. 3 and 4). However, it is possible to repeat this process either to increase or increase the widening or to create expanded pile parts at various suitable locations.

In the stage according to FIG. 3, a reinforcement basket can also be introduced into the pipe before concrete is refilled according to FIG. 4.

** WARNING ** End of CLMS field could overlap beginning of DESC **.