DE649132C - Method and device for the production of a foot broadening in the case of Ortpfaehlen - Google Patents

Description

Method and device for producing a foot enlargement Ortpfahlen There are several methods for producing a foot broadening Place stakes known. Partly it should be done by using extension drills or by parting off side recesses, i.e. by creating an unprotected one E ': cavity that is concreted out to be achieved. partly by pressing apart either the concrete directly or a footshell, e.g. B. a stretchable coat, the underground are displaced laterally.

With all of these methods it cannot be reliably determined the extent to which a widening of the foot has actually been achieved for the individual stake is. There are also the following disadvantages: The extension drill A created unprotected earth cavity can mainly be found in soil layers carrying groundwater in the period up to the pouring of the concrete and also during the concreting coincide in whole or in part. This just makes a totally undesirable one Loosening of the subsoil and harmful pollution and mixing of the brought in concrete with the fallen floor parts.

Are there particularly solid and stable soil layers in the subsoil, as a rule, you will lead the pile feet into these layers. The side Displacement of the subsurface by pressing apart brings it despite great effort no significant widening due to the passive resistance at the side.

. If a footshell, e.g. B. a stretchable or slit jacket, laterally pressed apart, it must as a result of the increase in its circumference slide tangentially on the surrounding ground. By pressing on the side of the mantle to the earth walls - but between the two there is a corresponding one great friction that prevents easy sliding and tearing of the jacket can lead, with disadvantages in a similar way as when falling behind Adjust cavities created for expansion devices.

Furthermore, the slit jacket, when it opens to the outside, must automatically increase its curvature. This requires that it be more flexible and thin-walled design must be used. When the soil layer into the the pole base comes to a standstill, e.g. B. is stony, the thin coat will be dented or damaged and prevents the achievement of a widening of the foot in whole or in part.

It is also important to guide the slotted or expandable jacket to the outside there is no guarantee that the widening of the foot will take place centrally. at solid ground on one side of the post and less solid on the other Naturally, the pile base becomes predominantly the more flexible one page widened. This causes undesirable and unfavorable off-center stress of the stake shaft.

The present invention avoids these 'disadvantages, also leaves a reliable measurement of the pile base width for each individual pile to and leads to a statically and structurally perfect form of the foot broadening. This is achieved according to the invention in that the front lower edge of the - to into the load-bearing subsurface of already sunk drilling or jacking pipe from a ring of iron planks or the like, which are slightly bent in the vertical direction and appropriately overlap each other with their edges, in the way in the underground is rammed or pressed that the wreath opens down in a goblet shape and in its protection the core of the earth located in its interior was brought out in any way and replaced by concrete.

The horizontal O_uschnittsforin the individual planks is in itself incidental. D: e once chosen and applied cross-sectional format is necessary not to go through any change of curvature or any other shape change when driving therefore not be used in a flexible, thin-walled design, but can be sufficiently strong, so that encountered stone obstacles and the like. can be punched through.

When driving in, the planks only displace the ground by so much than the strength of its wall. They are slightly curved in the vertical direction and slide, following the pressure exerted from above, avoiding sideways Displacements and pressures of the subsurface and the resulting friction down and out into the desired position. Also driving in the plank rim As a result, it is much easier to move into firmer types of soil as a lateral pressing apart of rings or sheaths.

The resulting downward-facing chalice shape conducts statically favorably and the compressive forces concentrated in the pile shaft without unnecessary material expenditure to the widened foot surface. Furthermore, there is a guarantee that the widening of the fula determined by measurement from above until after concreting of the cavity lying under the protection of the plank rim is no longer changed because the planks are held in place at the bottom by the subsurface and at the top by a head ring.

Lm a safe guidance of the planks during the pressing and a To achieve a central position of the same, the planks expediently according to the invention guided along vertical, inwardly slightly curved gauges while driving in, which rest on the inner casing wall. At 1 ¢ 11 when the plank rim is put on on it, under-round in the lower end of the drill pipe, lower ends of the planks in the correct position, namely as close as possible behind the drill pipe wall, they are according to the invention with clamps that are later when .Einrammen the planks peel off downwards, attached to the lower ends of the vertical gauges. the upper ends of the planks are according to the invention by a resilient head ring «-Supported horizontally and pressed outwards against the vertical gauges.

The doctrines linked together by rings are expediently put together with your clamped at the bottom by means of the clamps and at the top by the resilient head ring Pressed plank rim as a uniform basket from above into the sunk drill pipe introduced.

After the pile base has been concreted, the planks can either Remain in the ground or, best of all, be pulled individually after removing them beforehand the gauge basket and the head ring.

In the case of groundwater-bearing soil layers with fine grain, through Keeping the water level higher with the drill pipe compared to the groundwater level and flowing in finer soil particles can be prevented by the joints of the Bohlenniantel.

By inserting appropriate round iron reinforcement, the pile can also be used as a tension pole.

The drawing shows an embodiment.

Fig. I shows a section through a sunk drill pipe i, in which the plank wreath.2 together with the resilient head ring 3 and with the basket from vertical gauges 4 and horizontal connecting rings 5 is used. the lower plank ends are fastened with clamps 6 at the lower ends of the gauges .4. The cup shape to which the plank rim 2 widen when rammed in or pushed in is indicated by dashed lines.

Fig.2 shows the (cross-section according to a-, through Fig. I with the drill pipe i, the planks 2 and the vertical gauges 4.

Fig. 3 shows a section through the drill pipe i and the one already im Protection of the planks 2 made of a chalice-shaped shell It can be seen how by the resilient head ring 3, the upper ends of the Planks 2 have been led to the vertical -Lehrend. Fig.q. shows the cross-section according to c> d through Fig.3 with the open to the chalice-shaped jacket Plank wreath 2 and the-. for comparison, the drill pipe casing indicated in dotted lines i.

Claims (3)

PATENT CLAIMS: i. A method for the production of a foot broadening in place piles, characterized in that from the lower end of the sunk driving pipe a wreath of iron planks slightly bent in the vertical direction is rammed or pressed into the ground in such a way that the wreath opens in a goblet shape downwards, and that under the protection of the rammed-in rim, the core of the earth located in its interior is removed and replaced by concrete. 2. Device for carrying out the method according to claim i, characterized in that the plank rim is held together at the upper end by a resilient head ring (3), the Ramming in one consisting of inwardly curved rods (4.) and rings (5) Basket is led. 3. Apparatus according to claim z, characterized in that the Planks overlap in the guide cage with the edges and with these for the purpose of common Insertion into the drill pipe are temporarily connected by means of ferrules (6).