Method for producing a component free of toe pressure

Abstract

The invention relates to a method for producing a component, such as a structural member, free of toe pressure, including the steps of: introducing a soluble material into soil and introducing a component into the soil on the soluble material.

Claims

1. A method for producing a structural member with reduced, or that is free of, toe pressure, comprising: introducing a soluble material into a soil; and introducing the structural member into the soil on the soluble material, wherein one or more of the following: the soluble material is a frozen liquid; and the soluble material is introduced in several layers, wherein an intermediate liquid-permeable layer is introduced onto a layer with the soluble material.

2. The method according to claim 1, wherein the soluble material is a material with a solubility in water of at least 33 g/l water.

3. The method according to claim 1, wherein the soluble material is a material with a solubility in water of at least 100 g/l water.

4. The method according to claim 1, wherein after the structural member has been introduced, the structural member is subject to a rest period before undergoing an external load; wherein the soluble material at least partially dissolves during the rest period, thereby creating a cavity under the component.

5. The method according to claim 4, wherein the rest period is at least 4 days.

6. The method according to claim 4, wherein the rest period is at least 10 days.

7. The method according to claim 4, wherein the rest period is at least 20 days.

8. The method according to claim 1, further comprising forming a foundation hole in the soil; and wherein the foundation hole is filled with the soluble material as a soluble positioning element from a bottom of the foundation hole up to a target fill level.

9. The method according to any one of claim 1, wherein: before or during the introduction of the component, the soluble material is compacted such that the strength and/or the rigidity of the soluble material corresponds at least to the product of a height of the structural member and a weight of the structural member immediately after the introduction of the component.

10. The method according to claim 9, wherein the soluble material is compacted such that a width of the soluble material is equal to or greater than a width of the structural member to be created thereon and that a height of the soluble material corresponds to a maximum of the single width of the component.

11. The method according to claim 10, the height of the soluble material corresponds to a maximum of half the width of the component.

12. The method according to claim 1, wherein one or more of the following: the soluble material is selected from the group consisting of: salts, sugars, and acids; and the soluble material contains at least one liquid made of cellulose and one frozen liquid.

13. The method according to any one of claim 1, wherein a micro-element is added to the soluble material, the micro-element being selected from the group consisting of: zinc, manganese, iron, selenium, and copper.

14. The method according to claim 1, wherein the soluble material is selected from a material that, when completely dissolved in water, has a pH of at least 6.0 and a maximum pH of 8.0.

15. The method according to claim 1, wherein the soluble material is selected from a material that, when completely dissolved in water, has a pH of at least at least 6.8 and a maximum pH of 7.2.

16. The method according to claim 1, wherein a liquid is added to the soluble material before or after the introduction of the structural member such that cavities in the soluble material are filled with the liquid.

17. The method according to claim 1, wherein the soluble material is introduced into the soil, and the introduction of the structural member on the soluble material is performed by one of the following: immersion vibration, vibratory hammer, pipe jacking, and drilling a borehole.

18. The method according to any one of claim 1, wherein surface friction of the structural member is determined after the structural member has been introduced.

19. The method according to claim 18, wherein an additional structural member is introduced into the soil, wherein the additional structural member has same dimensions as the component, the additional structural member being introduced into the ground such that a toe pressure acts on the additional structural member from the ground; and wherein after the introduction of the further structural member a total resistance of the further structural member is determined; and wherein from the total resistance of the further structural member and the surface friction of the structural member the toe pressure resistance of the further structural member is determined.

20. The method according to claim 1, wherein the structural member is a component of a foundation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Preferred embodiments of the method according to the invention are described in the following figures. In the drawings:

(2) FIG. 1 shows a method according to the invention for producing a component with reduced or free of toe pressure in a first embodiment,

(3) A) after sinking a filling device,

(4) B) after introducing soluble material into the ground,

(5) C) after compacting the soluble material,

(6) D) while the component is being introduced on the soluble material,

(7) E) after manufacturing the component,

(8) F) after dissolving the soluble material;

(9) FIG. 2 shows a method according to the invention for producing a component with reduced or free of toe pressure in a second embodiment,

(10) A) after sinking a filling device,

(11) B) after introducing soluble material into the ground,

(12) C) while the component is being introduced on the soluble material,

(13) D) after manufacturing the component,

(14) E) after dissolving the soluble material;

(15) FIG. 3 shows a method according to the invention for producing a component with reduced or free of toe pressure in a third embodiment,

(16) A) after sinking a boring tool,

(17) B) after removing the boring tool,

(18) C) after introducing soluble material into the ground,

(19) D) while the component is being introduced on the soluble material,

(20) E) after manufacturing the component,

(21) F) after dissolving the soluble material; and

(22) FIG. 4 shows a method according to the invention for producing a component with reduced or free of toe pressure in a fourth embodiment,

(23) A) after introduced a first layer of soluble material into the ground,

(24) B) after introducing an intermediate layer of water-permeable material over the first layer of soluble material into the ground,

(25) C) after introducing a second layer of soluble material on the deposit of water-permeable material in the ground,

(26) D) during the introduction of the component on the soluble positioning element,

(27) E) after manufacturing the component,

(28) F) after dissolving the soluble material.

DETAILED DESCRIPTION

(29) A first embodiment of the method according to the invention is shown in FIGS. 1A to 1F, which are described jointly below. In the first process step V1 of the method according to the invention, a foundation hole 2 is worked into a soil 3 with a soil displacer 1, for example an immersion vibrator. The foundation hole 2 has a target depth T1. In the illustrated case, the width B2 of the foundation hole 2 largely corresponds to the width B1 of the soil displacer 1. It is also conceivable, especially if an immersion vibrator is used as the soil displacer 1, that the width B2 of the foundation hole 2 is greater than the width B1 of the soil displacer 1. The soil displacer can also be designed in the form of a pipe.

(30) After the target depth T1 has been reached by the soil displacer 1, the soil displacer 1 is moved out of the soil 3 by the target filling height H1 in a second process step V2. In parallel with this, a soluble material 4, in particular water-soluble material, such as rock salt and/or ice cubes, is introduced into the chamber 6 created through a sluice (not shown) at the head of the soil displacer 1. This can be done either solely through the weight of the soluble material 4 or additionally through the support of compressed air.

(31) In an optionally subsequent process step V3, the soluble material 4 is pressed or stuffed into the soil 3 by moving the soil displacer 1 up and down and, if necessary, compacted with the addition of further soluble material 4. The soluble material 4 forms a stable body 5 at the bottom of the foundation hole 2, on which a component 8 to be produced can be temporarily supported or positioned. To this extent, the soluble material 4 in this state can also be referred to as a support body or positioning element 5. Compaction leads to widening of the chamber 6 in a direction perpendicular to the movement of the soil displacer 1, so that a widened chamber 6′ is created which is completely filled by the positioning element 5. As a result of the widening, the widened chamber 6′ has a width B2′ which is greater than the width B2 of the foundation hole 2, and at the same time represents the width of the positioning element 5. The widened chamber 6′ or the positioning element 5 also has the actual filling level H1′, which, depending on the configuration of the compaction, can also differ from the target filling level H1 but may also be the same as the target filling level H1.

(32) In the following process step V4, the soil displacer 1 is lifted; into the cavity created in this way above the soluble material 4, the foundation material 7 of the building component 8 to be produced, for example cement, concrete, mortar, ballast and/or gravel, is introduced into the foundation hole 2 through the previously mentioned sluice at the head of the soil displacer 1, onto the soluble material 4 or the support body 5 and the foundation material 7 is compacted by moving the soil displacer 1 up and down. The procedure is repeated until the foundation hole 2 is filled with the foundation material 7 up to a desired height H2, in the present case up to the surface of the ground, and the component 8 is formed. This results in a jacket-like frictional contact between the foundation material 7 or the component 8 formed therefrom with the in-situ soil. The component 8 has a width B3 at the lower end, the base, which in the present case largely corresponds to the width B2 of the foundation hole 2. However, it is also conceivable that the width B3 is greater than the original width B2 of the foundation hole 2 due to the stuffing of the foundation material. In the present case, the width B3 at the base of the component 8 is smaller than the width B2′ of the positioning element 5 or the chamber 6′ filled thereby. This ensures that the component 8 rests completely on the soluble material 4 at the lower end. However, it is also conceivable that the width B3 at the base of the component 8 is smaller than the width B2′ of the positioning element 5 or the chamber 6′ filled thereby.

(33) Subsequently, in process step V5, a rest period is observed before the component 8 undergoes a significant external load. This means in particular that the component 8 is loaded with less than 10% of its load-bearing capacity. During this time, the soluble material 4 or the support body 5 is gradually dissolved by the moisture content of the soil 3 in the area of the widened chamber 6′. The rest period is chosen so that at the end of the rest period the soluble material 4 has dissolved, in the present case completely dissolved such that a cavity is formed below the component 8.

(34) In a final process step V6, the component 8 can then be subjected to a force F, wherein the component 8 is supported only by the surface friction between the lateral surface of the component 8 and the soil 3. A toe pressure cannot counteract the force F due to the at least partially empty chamber 6′ below the component 8. The force F can result, for example, from a structure or a building, in particular an above-ground building, which is to be supported by the component, or it can be applied mechanically or hydraulically for load-bearing capacity analysis of the component, in particular the surface friction.

(35) Alternatively, the immersion vibration method can be designed in such a way that method step V3 with the compaction of the soluble material 4 and the compaction of the foundation material 7 in method step 4a are omitted.

(36) By eliminating the compaction of the soluble material 4 in and of the foundation material 7, the alternative immersion vibration method can be used for time-efficient production of simple components. Due to the lack of compaction of the soluble material 4, the width B3 at the foot of the component 8 corresponds to the width B2 of the soluble material 4 or of the cavity formed as a result after it has been dissolved. So that the load from the weight of the component 8 on the soluble material 4, in particular directly after the foundation material 7 has been poured into the foundation hole 2, does not lead to an undesired high degree of compaction of the soluble material 4 and sagging of the component 8, the nature of the soluble material 4 can be selected such that a high bulk density of the soluble material 4 is achieved as soon as the soluble material 4 is filled. This can be achieved, for example, by a fine grain size and by the high flowability of the soluble material 4.

(37) A second embodiment of the method according to the invention for producing a component free of toe pressure is shown in FIGS. 2A to 2E, which are described jointly below. In a first process step V1a, a jacking pipe 12 with a width B5 is rammed, drilled, screwed or pressed into the soil 3 to a desired depth T1, so that a foundation hole 2 is formed that has a width B2. In a subsequent process step V2a, the soluble material 4 is added the foundation hole 2 through the core of the jacking pipe 12 via a sluice (not shown) of the jacking pipe 12 and the jacking pipe 12 is pulled a specific distance out of the soil 3. After the soluble material 4 has been introduced up to a filling level H1, in a further process step V4a the foundation material 7 is poured into the foundation hole 2 through the core of the jacking pipe 12 and the jacking pipe 12 is again pulled out of the soil 3. After the target height H2 has been reached, the jacking pipe 12 is completely removed from the foundation hole 2. The component 8 is thus formed from the introduced foundation material 7 and has a width B3 which is equal to the width B2 of the foundation hole 2. In a subsequent process step V5, analogously to the first embodiment of the method according to the invention, a rest period follows before the component 8 undergoes a significant load. Finally, in a method step V6, as already explained above, the component 8 can be loaded with a force F.

(38) A third embodiment of the method according to the invention for the production of a component free of toe pressure is shown in FIGS. 3A to 3F, which are described jointly below. In method step V1b, a boring tool 9 with the width B4 is used to drill a foundation hole 2 with a width B2 in the soil 3 to a target depth T1. When using a drilling method, the width B2 and the width B4 can be identical, i.e. there is no significant displacement of the soil, but material is discharged from the soil. However, this does not apply to what is known as a partial displacement drilling process, in which the larger core tube results in a certain lateral displacement of the in-situ ground. In parallel with the boring process, a support tube 10 is inserted from the bottom of the foundation hole 2 into the foundation hole 2 to below a target filling height H1. The support tube 10 prevents the lateral surface of the foundation hole 2 from being damaged during the introduction of the soluble material 4 and the foundation material 7 into the foundation hole 2, in particular prevents soil from being carried along into the foundation hole 2. It is also conceivable that such a support tube 10 is dispensed with. In this case, the foundation hole 2 can either be completely dispensed with or, instead of the support tube 10, a supporting liquid can be introduced into the foundation hole 2. In a subsequent method step V1b′, the boring tool 9 is pulled out of the foundation hole 2 and removed. The support tube 10 initially remains in the foundation hole 2.

(39) Subsequently, in method step V2b, a filling pipe 11 is introduced into the foundation hole 2, which has a funnel element at the upper end which opens into a guide tube having a smaller diameter than the width B2 of the foundation hole 2. The soluble material 4 is filled in through the filling pipe 11 up to the target filling height H1. However, it is also conceivable that the filling pipe 11 is dispensed with and instead the soluble material 4 is poured directly from the upper edge of the foundation hole 2 into the foundation hole 2. Subsequently, in method step V4b, the foundation material 7 is introduced above the soluble material 4 into the foundation hole 2 via the filling pipe 11 until the desired target height H2 above the soluble material 4 is reached. The support pipe 10 and the filling pipe 11 are continuously pulled out of the foundation hole 2 in this process. This can be done either in parallel or sequentially, wherein the support tube 10 can always be guided below a current filling level. If the foundation material 7 is introduced above the groundwater level, the filling pipe 11 can always be guided above the foundation material 7 that has been filled in. If the foundation material 7 is introduced below the groundwater level, a contract pipe can be used as the filling pipe 11 and guided in such a way that the outlet of the contract pipe is always immersed in the foundation material 7. This ensures that there is no intermixing of the foundation material 7 with the groundwater or supporting liquid. However, it is also conceivable that a filling pipe 11 is dispensed with and instead the foundation material 7 is poured directly from the upper edge of the foundation hole 2 into the foundation hole 2.

(40) In a method step V5, the support tube 10 and the filling pipe 11 are removed from the foundation hole 2 and, analogously to the procedure of the two aforementioned embodiments of the method according to the invention, a rest period is observed before the component 8 undergoes significant external stress. Finally, in a method step V6, as already explained above, the component 8 can be loaded with a force F.

(41) A fourth embodiment of the method according to the invention for producing a component free of toe pressure is shown in FIGS. 4A to 4F, which are described jointly below, which method largely resembles the second embodiment of the method according to the invention described above.

(42) In a modification to the second embodiment, in the fourth embodiment, a soluble positioning element 5′ is introduced into the ground such that a first layer 13 and a second layer 14 of the soluble material 4 are separated from one another by a water-permeable intermediate layer 15. In a first process step, which is not shown in the figures, analogously to the first process step Via of the second embodiment of the method according to the invention, a jacking pipe 12 is rammed, drilled, screwed or pressed into the soil 3 so that a foundation hole 2 is formed. In short, reference is therefore made at this point to the explanations relating to process V1a.

(43) In a subsequent process step V2c, which is represented in FIGS. 4A), 4B) and 4C) by the partial process steps V2′, V2c′″ and V2c′″, the first layer 13 of the soluble material is first added to the foundation hole 2 through a sluice (not shown) of the jacking pipe 12 and the jacking pipe 12 is pulled out of the soil 3 bit by bit. A water-permeable intermediate layer 15, which can also be referred to as a deposit, is then applied to the first layer 13 of the soluble material 4. The deposit 15 can have a coarse-grained material such as gravel or ballast, wherein the use of ice cubes is also possible. It is irrelevant whether the material of the deposit itself is soluble or not. A second layer 14 of the soluble material 4 is then applied to the deposit 15. The first layer 13 and the second layer 14 of the soluble material together with the water-permeable deposit 15 form a positioning element 5′ which extends from the bottom of the foundation hole 2 to a filling level H1.

(44) Subsequently, in a further process step V4c, the foundation material 7 is added to the foundation hole 2 through the core of the jacking pipe 12 and the jacking pipe 12 is pulled further out of the soil 3. After the target height H2 has been reached, the jacking pipe 12 is completely removed from the foundation hole 2. The component 8 is thus formed from the foundation material 7 that has been introduced and has a width B3 which, in the present embodiment, is equal to the width B2 of the foundation hole 2.

(45) In a subsequent process step V5c, analogously to the process step V5 of the first embodiment of the method according to the invention, a rest period follows before the component 8 undergoes a significant load. The rest period can be reduced here compared to the second embodiment of the method according to the invention, since groundwater can pass through the water-permeable insert 15 and the two layers 13, 14 of the soluble material 4 are each hydrated from several sides so that the soluble material 4 can dissolve more quickly. After the dissolving of the soluble material 4, the water-permeable deposit 15 settles in the bottom area of the foundation hole 2, so that the pile tip of the component 8 is released. Finally, in a method step V6, as already explained above, the component 8 can be loaded with a force F.

(46) It is understood that a multilayer positioning element according to the present embodiment according to FIG. 4 can also be used analogously in the method according to the invention according to FIGS. 1 to 3, in particular with a boring tool, a soil displacement tool or a combination thereof.

LIST OF REFERENCE NUMERALS

(47) 1 Soil displacer 2 Foundation hole 3 Soil 4 Water-soluble material 5 Positioning element 6, 6′ Chamber 7 Foundation material 8 Component 9 Boring tool 10 Support pipe 11 Filling pipe 12 Jacking pipe 13 First layer (4) 14 Second layer (4) 15 Intermediate layer B Width H Height T Depth