DE102009023553A1 - Method for prevention of setting phase of concrete with local concrete piles at pile head, involves bringing additive or displacement body to fresh concrete of pile head - Google Patents

Abstract

The method involves bringing an additive or displacement body to the fresh concrete of a pile head. The additive is mechanically or manually mixed under the concrete. The displacement body is mechanically or manually brought to the fresh concrete of the pile head.

Description

The The invention relates to the method for preventing the Abbindevorganges of concrete in cast-in-place piles at the pile head at a later time Caps of the pile head in the hardened Condition of the concrete to avoid or substantially facilitate.

at the production of in-situ concrete piles it is almost always required the concrete after concreting at the pile head to the required nominal height (= lower edge foundation, Sole or foundation beam) after curing and discard. This process is called caps. This clipping process can only after the earthworks (= exposing the pile head) done. To one damage to avoid the stake The earthworks started only after the concrete had hardened become. These earthworks are to be carried out with great care a damage below the pile head by pulling on the pile head (= break at lower pile shaft). For the cap, this means that the concrete at the pile head has hardened very far and thus very labor-intensive must be cut by caulking with a jackhammer. The required Kapplänge results itself from the distance between the desired height and excess concrete over it. ever according to drilling, pressing, vibration or piling method of in-situ concrete piles this measure very much differently. Also influence the technical requirements of the building this length. Usually this length is between 0.30 m and 2.00 m. lengths up to 7 m and longer are possible. The diameters of the piles are usually between 0.30 m and 2.00 m.

It it is known that it already hydraulic cutting machines to facilitate work, who hangs on an excavator be there. The space conditions but on the Bastelle do not always allow this. A disposal of the Kappgutes remains.

It it is known that the upper one later To be cut concrete in the so-called "fresh state" by means of excavators can be processed. After that, depending on quality and feasibility the execution no or only a small rework required. This Working "Fresh in Frisch " However, for site-technical reasons very often not possible.

It is not technically possible just the concrete for the pile head area in advance with additives in the concrete mixer or in the concrete pump due to the size of the concrete mixer or the length the concrete hoses through the pumped is never exactly the concrete with the additives can be pumped really fit at the pile head.

disadvantage the capping works on the hardened Concrete is the labor-intensive caulking, which is very careful be executed and time-consuming earthworks before capping around the pile head, with the big one Risk of damage by the excavator and the disposal of the Kappgutes.

task The invention is the labor-intensive and expensive Kappvorgang after the curing phase prevent or facilitate the concrete. Likewise, by the invention the time-consuming earthworks around the pile head around be relieved. The expensive Kappgutentsorgung can through the invention omitted or substantially reduced.

By the introduction of additives or displacement bodies after the concreting process in the fresh concrete or slightly "tightened" concrete at the pile head to prevent or reduce the curing process on normally to be capped pile head, the object of the invention solved.

By preventing hardening Is it possible on the time-consuming and costly Kapparbeiten whole or in part to refrain or the work is much easier. The Disposal of the Kappgutes deleted completely or partially. The earthworks around the pile head are around much easier, because not worked with such a great care got to. The risk of damaging the Stake is much lower because the excavator is not an attack point (= hardened Concrete).

Example description of a Patent application

embodiments The invention are illustrated in the drawings and are in following described.

It demonstrate

1 : A manufactured in-situ concrete pile in longitudinal section

2 : A manufactured and in the pile head area excavated Ortbetonpfahl in longitudinal section

3 : A manufactured and in the pile head area excavated and capped in-situ concrete pile in longitudinal section

4 : A prepared and cut in the Pfahlkopfbereich excavated and capped cast-in pile with concrete foundation in longitudinal section

5 : A manufactured cast-in pile in longitudinal section with added additives

6 : A prepared in-situ concrete pile in longitudinal section with introduced displacement bodies

The 1 - 4 show the state of the art:
In 1 is a finished cast-in-place pile 1 in the ground 11 with reinforcement 2 shown. Until the foundation 4 , a foundation beam or a sole can be concreted, the size of the foundation around the pile head must be according to 2 be excavated. This work can be done only after the hardening of the concrete. At an early stage, the dredgers on the sides would push and damage the still fresh concrete sideways due to the traffic load. Also, the dredging work should be done very carefully so that the pile is not damaged. After the excavation work, the cleanliness layer 3 built-in. In the 3 is the pile cap cut and the Kappgut 5 is stored sideways for further disposal. The reinforcement 2 looks up out of the capped pole. Subsequently, the foundation can 4 be concreted on the capped pile ( 4 ).

The 5 - 6 show the invention:
In the 5 is after the production of cast-in-place pile (as in 1 ) mechanically or manually an additive 6 which prevents the setting, the easily "tightened" concrete breaks again or delays the setting process by many days until the earthworks are done. The depth of insertion 7 depends on the later lower edge of the foundation 4 , The introduction can be done by stirring by whisk, by hand or by pressure by means of jet (water or air). Here everything can be used technically which makes the introduction easier or possible. Even only water to reduce the quality of the concrete would make the work much easier.

In the 6 is after making the in-situ concrete pile as in 1 mechanically or manually a displacement body z. B. in the form of an inflatable bladder 8th or a styrofoam body 9 etc. set in the fresh concrete. This area then no longer has to be cut later or the existing edge concrete 10 is only very thin and thus easy to remove. Here everything can be used technically which makes the introduction easier or possible. Even injected Styrofoam balls to reduce the quality of concrete would make the Kapparbeiten much easier.

Claims (5)

A method for preventing the Abbindevorganges of concrete Ortbetonpfählen the pile head, characterized in that an additive 6 or displacement body ( 8th + 9 ) is introduced into the fresh concrete of the pile head to prevent or facilitate the Kappvorgang. Method according to claim 1, characterized in that the additive ( 6 ) is mixed mechanically or manually under the concrete. Method according to claim 1, characterized in that the displacement body ( 8th or 9 ) is introduced mechanically or manually into the fresh concrete of the pile head and thus displaces the concrete and reduces the concrete volume. Method according to claim 1 or 2, characterized that the admixture can be anything that the setting of concrete prevents or the concrete quality reduced. Method according to claim 1 or 3, characterized that the repressive body is everything what can displace the concrete or the concrete quality significantly reduced.