Pile for Foundation

Abstract

The device includes the body (1), provided with a helix (3) on the bottom end, and of an ending (4) on the top part of the body (1). The diameter of the helix (3) is in the range of 1.0 to 100 times the diameter of the body (1) and/or of the least transversal dimension of the body (1). The body (1) has a closed or open profile on the cross section, with the body (1) having one profile at least. The pitch of the helix (3) is in the range of 0.1% to 90% with the pitch being linear or variable along the length of the helix and the length of the blade of the helix (3) being 5° at least of the circumference of the body (1) and the drilling base being provided with one helix (3) at least. On the bottom end, the body is provided with a pricker (2), with the pricker (2) being bevelled into one surface at least on the bottom end at the angel in the range of 90° to 0.1° towards the vertical axis of the drilling base and/or with the bottom end of the pricker (2) having a semi-spherical shape.

Description

TECHNICAL FIELD

The device belongs in the field of building industry, i.e. in concrete terms, in launching projects to establish buildings located on piles.

BACKGROUND ART

The piles for lying foundations for buildings can be installed as combined with earthworks. In practice, such a pile is inserted into a hole, excavated in the soil beforehand, where it is neither set nor rectified however. To set and rectify the pile, the space between the pile and the hole wall must be filled e.g. with concrete. This solution is disadvantageous due to the necessity both of excavating (drilling) works, to make a hole in the soil, and of concreting the space remaining later after the pile insertion. Therefore, this solution is not suitable from economical or ecological points of view.

Another way to install piles for foundation of buildings is to drill them into the soil. The hitherto known system of installing the piles by means of drilling in is known e.g. from the document PUV 2005-16435. This document describes a drilling base provided, on its bottom end, with a twist drill mounted on a shaft where the shaft is widened, on the top edge level of the drill, into the top tube part by a conical section. The twist drill has equal blade areas in its whole length and is made only in the extent of 360° on the shaft. This arrangement results in problematic setting of the drilling base in a rocky soil where the twist drill can be clogged with stones. Due to clogging, the base gives up drilling deep into the soil and, if not stopped by the operating personnel, the twist drill will be totally destructed by acting of pressure.

DISCLOSURE OF INVENTION

The main substance of the proposed technical solution is based on shaping the helix blade of the drilling base. The drilling base has one helix blade at least. In case the drilling base is provided with one helix only, the helix is located on the body bottom part of the drilling base. The helix diameter is in the range of 1.0 up to 100 multiple of the body diameter and/or of least transversal dimension thereof. The helix diameter, and due to it also the surface of its blade, is constant and/or variable lengthwise. E.g. the helix diameter can increase upwards from bottom. The helix pitch is given from 0.1% to 90%. Due to this extent again, diverse variants of the drilling bases can be made for various kinds of soil or possibly for various types of considered over-ground devices attached to the drilling base. The length of the helix blade is 5° of circumference of the body at least. The harder is the soil in the place of the drilling base installation the greater is the weight of the over-ground device and the more intensive is the expected influence of climatic conditions, the greater must be the helix blade length. It appears advantageous if the helix blade is longer than 360°. Besides, the body can be provided with more helix blades. The helix pitch can be linear and/or variable.

In an alternative solution the drilling base can be provided with a pricker located on the body bottom part, said pricker forming the bottom end of the drilling base. Then, the helix is located either on the drilling base body or on the pricker. The pricker bottom end is sharpened into one surface at least, namely at the angle of 90°-0.1° from the vertical axis of the drilling base. In an alternative solution, the pricker bottom can have semi-spherical end. The variant of the pricker end is chosen in accordance with the pricker diameter and with the kind of soil into which the drilling base is installed. The pricker can be free or provided with a helix. By means of this solution, diverse variants of the drilling base can be made which differ by the helix-to-body diameter ratio. In consequence of it, these various drilling bases can be utilized for diverse kind of soils (sandy, stony, or claylike ones), with the greater-helix-diameter drilling bases being applicable in soft soils especially, e.g. in peat.

The body can have a closed or also open profile in the perpendicular cross section. The choice of the profile, of its diameter and wall thickness is influenced by the soil kind into which the drilling base has to be set. In some cases the body can have a polygonal shape in the perpendicular cross section. Although the drilling base, with a body shaped as a polygon, is difficult to set, it offers better support in the soil against climatic influences. Equally, the body can be composed of more mutually connected profiles where open profiles can be combined with the closed ones and the round cross sections can be combined with polygonal ones etc.

In some cases, the drilling base body can be shaped so that it has smaller diameter in the bottom part than in its top part. The body can be widened linearly and/or stepwise towards the top part. With the stepwise widening, an auxiliary helix is located on the transition between parts having different diameters. The auxiliary helix enables to drill the greater-diameter body top part into the terrain. If greater side forces are assumed to act on the drilling base, the body can be provided with an auxiliary ring. The auxiliary ring is mounted in such place of the body that it will be situated beneath the soil surface with the drilling base being drilled-in. The auxiliary ring is attached to the drilling base body by means of a wire weave and serves for usage in a soft under-bed. For the usage in a hard rocky under-bed, the auxiliary ring is attached to the drilling base body by means of inclined felloes. Instead of being filled up with excavation soil, the space in the auxiliary ring can be possibly set in concrete afterwards.

Another possibility to improve the resistance of the drilled-in drilling base against side forces is to make a welded wire thread around the whole body to increase the friction between the drilling base body and the soil in which the drilling base is located.

Alternatively, the body top ending can contain a rectifying element to enable to throw the column or the device (e.g. a solar panel) out of parallel which are installed on the drilling base afterwards. In practice as a rule, several screws passing through nuts, welded to orifices in the body covering, are used as rectifying elements. The rectifying element is applied in the case the drilling base cannot be drilled wholly vertically into the required position, especially in stony soil.

Another ending can be shaped as a flange perpendicular to the drilling base body. On the circumference, the flange has orifices for screws to attach a device which is installed on the drilling base.

BRIEF DESCRIPTION OF DRAWINGS

Exemplary realizations of the proposed solution are described with reference on following drawings:

FIG. 1—Fundamental embodiment of the drilling base,

FIG. 2—Alternative solution with an auxiliary ring attached with felloes and with an auxiliary helix,

FIG. 3—Alternative solution with the auxiliary ring attached with a wire weave and with the auxiliary helix,

FIG. 4—Alternative solution of the small-diameter drilling base with the rectification,

FIG. 5—Alternative solution of the drilling base with flange-type ending,

FIG. 6—The drilling base composed of several profiles and helices on the body and on the pricker,

FIG. 7—The drilling base without a pricker and with several differently long helices on the body.

BEST MODE FOR CARRYING OUT THE INVENTION

Example 1

The drilling base, made conformably to the presented technical solution, consists of the 1650 mm long body 1 with a diameter of 114 mm. The body 1 is provided with the helix 3 on its bottom end. The helix 3 is located above the pricker 2 which forms the bottom part of the drilling base. The blade area of the helix 3 widens from the pricker 2 towards the ending 4 which forms the top part of the drilling base. In this case the blade of the helix 3 is 25 mm wide at the pricker 2 and 90 mm wide on the top end of the helix 3. The helix 3 has the extent of 450°. The described device is evident on the FIG. 1.

Example 2

The drilling base, made in accordance with the presented technical solution, has total length of 4800 mm with the body bottom part 1a being 2600 mm long and having the diameter of 219 mm. The body top part 1b is 1800 mm long with the diameter of 360 mm. In this case, the transition 9 is 200 mm long. On the bottom end the body 1 is provided with the helix 3. The helix 3 is located above the pricker 2 which forms the bottom part of the drilling base. The blade area of the helix 3 widens from the pricker 2 towards the ending 4 which forms the top part of the drilling base. In this case the blade of the helix 3 is 50 mm wide at the pricker 2 and 120 mm wide on the top end of the helix 3. The helix 3 has the extent of 450°. The auxiliary helix 7 is located on the transition 9. Above the transition 9 the auxiliary ring 5 is attached on the body top part 1b by means of the wire weave 11. On the body top part 1b the auxiliary ring 5 is mounted so high that it is to be found under the earth surface with the base being drilled in. The part of the body 1, located under the earth surface after the base setting, is provided with the wire 8 on its surface, said wire 8 being shaped to form a thread on the body 1 of the drilling base.

In this case the ending 4 is adapted, by means rectification brackets 6 in a form of screws and nuts 12, to assemble a tracker which is used to support a solar panel.

The described device can be seen on the FIG. 3.

Example 3

The drilling base, according to the proposed technical solution, consists of the body 1 with the pricker 2 situated on the bottom end. In this case the body 1 consists of more profiles with different diameters and the bottom part of the pricker 2 is bevelled by one skew cut at the angle of 45° towards the vertical axis of the drilling base. To the pricker 2 the conical part of the body 1 is coupled on which the cylindrical part of the body 1 is located consisting of a steel tube. On the pricker 2 and on the conical part the helix 3 is placed. The prolongation of the helix 3 to the pricker 2 and the form of the pricker 2 facilitate to locate the drilling base into very hard soil. In the present case, this helix 3 has the pitch of 15% with the area of its blade and its diameter increasing from the bottom part of the drilling base towards the ending 4. The first helix is 540° long and its maximum diameter equals 1.9 times the diameter of the given part of the body 1. To the cylindrical part of the body 1, further conical part or the transition 9, are coupled respectively. On the transition 9, the auxiliary helix 7 is placed. The auxiliary helix 7 is 360° long, its pitch equals 15% and the area of its blade does not change lengthwise. The diameter of the auxiliary helix 7 equals 1.3 times the given part of the body 1. On the transition 9, the body top part 1b links up which consists of a close steel hexagonally shaped profile.

The described solution is obvious on the FIG. 6.

Example 4

The drilling base, in accordance with the proposed technical solution, is composed of the body 1 consisting of one profile. On the bottom part of the body 1 a cone is located which is rounded on the bottom end. In this case, on the cone the helix 3 is located the pitch of which is 25% and the length is 360°. The area of the blade of the helix 3 and its diameter as well increase from the bottom part of the drilling base towards the ending 4 in this case. In this case, the maximum diameter of the helix 3 is 2.8 times the diameter of the given part of the body 1. On the cylindrical part of the body 1, several other helices 3 are located. These further helices 3 have the length of 50° and the pitch of 25%. The base drafted in such a way is suitable to support light over-ground devices in very soft soils.

The described solution can be seen on the FIG. 7.

LIST OF REFERENCE SYMBOLS

• 1—body
• 1a—body bottom part
• 1b—body top part
• 2—pricker
• 3—helix
• 4—ending
• 5—auxiliary ring
• 6—rectification bracket
• 7—auxiliary helix
• 8—wire
• 9—transition
• 10—felloe
• 11—wire weave
• 12—nut
• 13—flange

Claims

1. (canceled)

2. (canceled)

3. (canceled)

4. (canceled)

5. (canceled)

6. (canceled)

7. (canceled)

8. (canceled)

9. (canceled)

10. (canceled)

11. (canceled)

12. (canceled)

13. (canceled)

14. (canceled)

15. (canceled)

16. (canceled)

17. (canceled)

18. A pile for a foundation comprising:

a body having a bottom end and a top end, at least one helix provided on the bottom end of the body, the top end including an ending;

wherein the helix has an blade having a diameter and the body has a diameter and/or least transversal dimension, the diameter of the helix being between about 1.0 to 100 times the diameter and/or least transversal dimension of the body, and

wherein the body has a cross-section and a closed or open profile on the cross-section, the body having at least one profile, and

wherein the pitch of the helix is in the range of 0.1% to 90%, with the pitch being linear or variable in the length of the helix, and

wherein the length of the blade of the helix is at least 5° of the circumference of the body, and

wherein the body has a surface which is eventually provided with a wire above the helix, with said wire being shaped to form a thread on the surface of the body, and

wherein the surface of the body is provided with the wire below the helix, with said wire being shaped to form a thread on the surface of the body.

19. A pile for a foundation according to claim 18, wherein the body is provided with a pricker on the bottom end, with the pricker being bevelled into one surface at least on the bottom part, with an angle of said bevelled surface being in the range of 90° to 0.1° toward the vertical axis of the drilling base.

20. A pile for a foundation according to claim 18, wherein the body is provided with a pricker on the bottom end, and wherein the bottom part of the pricker has a semi-spherical shape.

21. A pile for a foundation according to claim 18, wherein the pile is provided with an auxiliary ring on the top end of the body below the ending.

22. A pile for a foundation according to claim 18, wherein the ending is provided with a rectification bracket.

23. A pile for a foundation according to claim 22, wherein the rectification bracket is shaped as a nut.

24. A pile for a foundation according to claim 18, wherein the ending is shaped as a tube.

25. A pile for a foundation according to claim 18, wherein the ending is shaped as a flange.

26. A pile for a foundation according to claim 18, wherein the bottom end of the body has a smaller diameter than the top end of the body, and wherein an auxiliary helix is located on a transition between the bottom end and the top end.

27. A pile for a foundation according to claim 19, wherein an auxiliary ring is provided on the body top part below the ending.

28. A pile for a foundation according to claim 19, wherein the ending is provided with a rectification bracket.

29. A pile for a foundation according to claim 28, wherein the rectification bracket is shaped as a nut.

30. A pile for a foundation according to claim 19, wherein the ending is shaped as a tube.

31. A pile for a foundation according to claim 9, wherein the ending is shaped as a flange.

32. A pile for a foundation according to claim 19, wherein the bottom end of the body has a smaller diameter than a top end of the body, and further including an auxiliary helix located on a transition between the bottom end and the top end.