Patent Application
20070012482
The present invention relates to a method for drilling, in particular percussion drilling or rotary percussion drilling, a hole in soil or rock material and for forming an anchoring in said hole, wherein a borehole is formed by the introduction of a drill bit mounted on a drill rod assembly and a jacket tube is introduced into the borehole during the drilling procedure, wherein the drill rod assembly is separated from the drill bit and removed from the borehole upon completion of the borehole. The invention further relates to a device for drilling, in particular percussion drilling or rotary percussion drilling, a hole in soil or rock material and for forming an anchoring, wherein a borehole is formed by the introduction of a drill bit and a jacket tube is introduced into the borehole during the drilling procedure, wherein the drill rod assembly is separated from the drill bit and removed from the borehole upon completion of the borehole.
From DE 14 84 440 A1 a method for drilling a hole and for forming an anchoring in the hole is known, wherein a bore hole is formed by the introduction of a drill bit mounted on a drill rod assembly and a jacket tube is introduced into the bore hole during the drilling procedure, wherein the drill rod assembly is separated from the drill bit and removed from the bore hole upon completion of the bore hole, wherein a curable fluid is introduced in a space between the jacket tube and the bore hole wall, wherein the jacket tube is secured on the curable fluid and wherein after curing of this fluid the jacket tube is pretensioned. Furthermore, from FR 1 375 895 A the pretensioning of the jacket tube before curing a curable fluid is known.
In the context of the production of a hole or borehole in soil or rock material and the subsequent formation or fixation of an anchoring or lining in the borehole, it is, for instance, known from WO 98/21439 and WO 98/58132 to introduce a jacket tube into the borehole during the drilling procedure, for instance percussion drilling or rotary percussion drilling, whereupon, after the completion of the bore, optionally a part of the drill bit is removed from the borehole together with the drill rod assembly, while the jacket tube remains in the borehole such that an anchor will subsequently be formed within the borehole by filling a curing mass into the same. According to the configuration set out in WO 98/58132, the drill rod assembly can be provided with additional ribs and grooves on its outer periphery in order to provide an accordingly good anchoring effect with the drill rod assembly remaining in the borehole and being subsequent filled.
Alternatively, it is known, after the production of a borehole, to remove the drilling tool together with the drill rod assembly from the borehole, whereupon an anchor or anchoring means usg subsequently introduced into the borehole, wherein it is, for instance, referred to EP-A 0 079 875, EP-B 0 047 727, EP-B 0 207 030, EP-B 0 016 742, EP-A 0 077 762, WO 97/31177, EP-A 0 112 316, WO 91/06713, DE-A 40 24 869 or U.S. Pat. No. 4,636,115. In that known prior art, after the completion of a borehole and subsequent removal of the drilling device, expandable anchoring elements are introduced into the borehole, which are kept at a reduced diameter relative to the borehole during their introduction into the borehole, whereupon, after the complete introduction into the borehole, expandable partial regions of the anchoring device, which are folded during the introduction or generally reduced in terms of cross section, are expanded.
Furthermore, anchor or tension rod configurations or methods for fixing the same in soil or rock material can, for instance, be taken from DE 693 918, FR 816 086, DE 1 104 905 or DE 1 484 572, said anchor elements being again introduced substantially after the completion of a borehole and subsequent removal of the drilling device.
That known prior art, in particular, involves the drawback that the borehole must be produced in a first method step, whereupon, after the removal of the drilling tool together with the drill rod assembly, the anchoring device is introduced into the optionally very long borehole in a further method step. It is immediately apparent that the two separate operating steps not only require accordingly more time, but that optionally the subsequent introduction of such an anchoring device having a great length may entail problems. Furthermore, it is to be anticipated that the removal of the drilling device together with the drill rod assembly and the subsequent introduction of an anchoring device is feasible only in comparatively solid soil or rock, where it must be safeguarded that no material will break into the borehole, for instance, during the drilling procedure or after the removal of the drilling tool and prior to the final introduction of the anchoring device, which would block the borehole and, hence, render the introduction of the anchoring device impossible.
Moreover, it is, for instance, known to arrange so-called packers about the outer periphery of the drill rod assembly of a drilling device, which enable an expansion into abutment on the borehole wall over a short partial region upon completion of the bore, thus acting against an extraction or removal of the drill rod assembly from the borehole. By means of such packers, it is, however, impossible to provide a reliable anchoring effect intended to stabilize the surrounding soil or rock material, particularly where a plurality of anchors to be adjacently arranged are provided, so that additional anchoring means such as, for instance, the application of a curing material will optionally have to be provided.
Departing from the prior art mentioned in the beginning, the present invention aims to provide a method and device of the initially defined kind, which enable the formation of an anchoring immediately after the completion of a borehole, in particular, to stabilize the surrounding soil or rock material, yet with a simplified overall construction and, in particular, reduced time expenditure.
To solve these objects, a method of the initially defined kind is essentially characterized in that the jacket tube is secured to the borehole wall particularly in the end region facing the borehole interior, that a curable fluid is fed into a free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall, and that tensioning of the anchor-forming jacket tube is effected prior to the final solidification of the curable fluid. Due to the fact that, according to the invention, the securement of the jacket tube to the borehole wall and the introduction of a curable fluid into a free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall are effected upon completion of the borehole and removal of the drill rod assembly and, optionally, part of the drill bit, a stabilization and compaction of the surrounding soil or rock material are immediately feasible during the subsequent tensioning or bracing of the anchor-forming jacket tube. It is, thus, ensured that a curable fluid introduced into the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall is appropriately solidified by the tensioning of the anchor-forming jacket tube, and that the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall is reliably and completely filled with the curable fluid so as to obtain the desired connection between the jacket tube or anchor and the surrounding soil or rock material as well as the anchoring effect and stabilization and compaction of optionally different soil and rock layers through which the anchor formed by the jacket tube is passed.
A simple and reliable introduction of the curable fluid into the annular-space-forming free space between the outer periphery of the jacket tube and the surrounding borehole inner wall is achieved according to a preferred embodiment in that the curable fluid is introduced into the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall via passage openings provided about the periphery of the jacket tube. The curable fluid can, thus, be introduced through the interior of the jacket tube, reaching the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall through passage openings provided about the periphery of the jacket tube, so that the complete filling of the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall will be safely ensured even in the event of optionally large borehole lengths. It is, therefore, not necessary to introduce a curable material, for instance, from the outer side of the jacket tube or anchor into the free space provided between the jacket tube and the borehole inner wall and optionally having a large diameter or cross section.
For a particularly reliable introduction of curable material through the passage openings provided about the periphery of the jacket tube, it is proposed according to a further preferred embodiment that the curable fluid is fed through the interior of the jacket tube via a supply duct introduced into the interior of the jacket tube and having supply duct feed openings provided in the region of the passage openings of the jacket tube.
Particularly if the filling with a curable fluid, of the interior defined by the anchor-forming jacket tube is not required or reasonable, it is proposed according to a further preferred embodiment that sealing elements for sealing the annular space formed between the outer periphery of the supply duct and the inner periphery of the jacket tube are provided on the outer periphery of the supply duct for the curable fluid, in the vicinity of the feed openings for the curable fluid, whereby it is safeguarded that the curable fluid will reach the respective regions of the passage openings of the jacket tube and be reliably fed into the free space between the jacket tube and the borehole inner wall via said passage openings in order to enable the proper anchorage of the jacket tube in the curing material and in the bond with the surrounding soil and rock material.
To support the anchoring effect by the anchor-forming jacket tube during the tensioning of the latter, it is proposed according to a further preferred embodiment that that the jacket tube is designed to have an outer diameter increasing or widening towards the borehole interior at least on its outer periphery. Such a widening or increasing diameter provides an appropriate wedge effect in the tensioning to be performed, so as to ensure the reliable compaction and filling of the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall with the curable fluid prior to its final solidification and, hence, an enhanced anchoring effect.
An increasing or enlarging diameter of the jacket tube in the direction of the borehole interior will, for instance, be obtained in that the jacket tube is comprised of mutually telescopically insertable jacket tube elements forming step-like regions on the outer periphery, as in accordance with a further preferred embodiment of the invention. In this manner, not only reliable tensioning while distributing the curable material introduced into the free space between the jacket tube and the borehole inner wall is feasible, but also cumbersome operating steps involved in the extension of a jacket tube in the event of large borehole lengths will be avoided, since the individual jacket tube sections or elements are telescopically inserted or insertable into each other and extractable with the borehole length progressing.
If the forces introduced through the jacket tube during tensioning while taking into account the curable material fed into the free space between the outer diameter of the jacket tube and the borehole inner wall are insufficiently high, it is provided according to a further preferred embodiment, in order to increase the anchoring effect, that an additional anchorage is introduced into the interior of the anchor-forming jacket tube.
For the reliable introduction of such an additional anchorage even in the event of large borehole lengths, it is, moreover, provided in a preferred manner that the additional anchorage is guided on the inner periphery of the jacket tube, particularly on its end facing the borehole interior.
In order to guarantee the anchoring effect provided by the additional anchorage, it is contemplated according to a further preferred embodiment that the additional anchorage is fixed or anchored to the drill bit and/or, in the region of the guidance, to the jacket tube inner wall.
In order to further assist the anchoring effect when using an additional anchoring element, it is proposed according to a further preferred embodiment that the interior of the jacket tube is filled with a curable fluid after the introduction of said additional anchorage.
To solve the objects set out in the beginning, a device of the initially defined kind, moreover, is essentially characterized in that the anchor-forming jacket tube on its periphery is formed with a plurality of passage openings for feeding a curable material into a free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall, that a tensioning means for the anchor, in particular an anchor plate and a screw capable of being screwed onto the jacket tube, is fixable to the jacket tube end projecting out of the borehole, and that anchoring or fixing elements for anchoring the jacket tube to the surrounding borehole inner wall are provided, particularly in the jacket tube end region facing the drill bit. As already indicated above, a structurally simple construction, thus, helps ensure that the anchor-forming jacket tube, after the completion of a borehole and removal of the drill rod assembly, and optionally partial removal of the drill bit, is reliably secured particularly on its end facing the borehole interior, whereupon, after the introduction of a curable fluid or material into the free space between the outer diameter of the jacket tube and the borehole inner wall, tensioning by the aid of a tensioning device has become feasible. In a manner known per se, such a tension device may, for instance, be comprised of a tension plate contacting the anchor-forming jacket tube outside of the borehole as well as an appropriate screw connection.
For a particularly reliable feeding of the curable fluid into the free space between the outer periphery of the jacket tube and the borehole inner wall, it is proposed according to a preferred embodiment that the curable fluid is feedable through the interior of the jacket tube via a supply duct introduced into the interior of the jacket tube and having supply duct feed openings provided in the region of the passage openings of the jacket tube. In this manner, not only the reliable feeding of curable material will be ensured, but also feasible a selected feeding of curable material will be feasible by using a supply duct which, in particular, can be removed again after the introduction of the curable material.
In this context, it is proposed according to a further preferred embodiment that sealing elements for sealing the annular space formed between the outer periphery of the supply duct and the inner periphery of the jacket tube are provided on the outer periphery of the supply duct for the curable fluid, in the vicinity of the feed openings for the curable fluid. It will thereby be safeguarded that the curable material to be fed into the free space between the outer periphery of the jacket tube and the inner periphery of the borehole wall can be substantially supplied in the region of the passage openings of the jacket tube.
As already indicated above, the anchoring effect can be supported by providing a diameter of the anchor-forming jacket tube, that increases, in particular, towards the borehole inner wall, wherein in this context it is proposed according to a further preferred embodiment that the jacket tube is comprised of mutually telescopically insertable jacket tube elements having their outer peripheries or diameters decreasing from the jacket tube end arranged in the borehole interior. Such jacket tube elements which are telescopically insertable into each other will not only enhance or increase the anchoring effect in cooperation with the curable fluid, but also render cumbersome operating steps involved required for the extension of a jacket tube in the event of large borehole lengths superfluous on account of the mutually telescopically insertable jacket tube elements.
To ensure the proper positioning of the adjoining or mutually insertable, telescopic jacket tube elements, it is proposed according to a further preferred embodiment that the telescopic jacket tube elements are each formed in their end regions with cooperating stops or stop surfaces. Such stops or stop surfaces in addition enable the adjustment of a defined length of the anchor-forming jacket tube during tensioning by partially extracting the anchor-forming jacket tube and, hence, the obtainment of the desired anchoring or tensioning effect.
In order to prevent the direct impact of mutually cooperating stops or stop surfaces, which, for the transmission of appropriate forces, at least partially have boundary surfaces extending substantially normally to the axis of the borehole, it is provided according to a further preferred embodiment that wedge-shaped abutment surfaces enclosing acute angles with the axis of the jacket tube are provided in the region of the ends of the jacket tube elements. Such wedge-shaped abutment surfaces cause the continuous increase of, for instance, frictional forces of mutually cooperating stop surfaces such that instantaneous or impact-like stresses in the region of the stops or stop surfaces will be avoided.
For the reliable and adequate securement or fixation of the anchor-forming jacket tube particularly in the end facing the borehole interior, it is provided according to a further preferred embodiment that the fixing elements are comprised of at least one hook or the like, in particular foldout hook, which projects from the outer periphery of the jacket tube. Such hooks will penetrate into the surrounding rock or soil material and, hence, provide securement upon tensioning of the jacket tube. By arranging the pivot axes of the hooks, in particular, on the hook ends facing the borehole interior, the substantially automatic emergence of the hooks will be caused by the retraction of the jacket tube during tensioning, so that no additional and optionally expensive mechanisms for bringing out or extracting the fixing or anchoring elements will be required.
To support the anchoring effect, it is provided according to a further preferred embodiment that an additional anchoring element is introducible into the interior of the jacket tube.
For the reliable and proper introduction of such an additional anchoring element, it is provided according to a further embodiment that the additional anchoring element comprises a guide on its end facing the borehole interior, which guide is arranged, in particular slidingly arranged, along the inner wall of the jacket tube.
In order to separately introduce a tensioning force onto the device according to the invention by the additional anchorage too, it is provided according to a further preferred embodiment that the additional anchorage is comprised of a solid rod provided, in particular, with an external profile. The improvement or enhancement of the anchoring performance to be attained by the additional anchorage, departing from a solid rod having a substantially smooth surface, can be further enhanced by using a solid rod having, for instance, a thread-like external profile, in which case it is preferred to additionally fill the hollow space of the jacket tube or anchor as already indicated above, so that the anchoring effect will be supported and increased by the combined action with the profiled outer surface.
In the context of increasing the anchoring effect by using an additional anchorage, it is provided according to a further preferred embodiment that the additional anchorage is fixable or anchorable to the drill bit and/or, in the region of the guide, to the jacket tube inner wall, so as to enable the safe and reliable fixation of the additional anchorage in the anchor-forming jacket tube even with optionally large borehole lengths.
In particular, with a configuration of the anchor-forming jacket tube having a diameter widening towards the borehole interior by the stepwisely adjoining, telescopic jacket tube elements, and optionally by providing the additional anchorage, an accordingly high anchoring effect will be obtained with jacket tube elements having substantially smooth surfaces while, at the same time, taking into account the curable fluid introduced into the free space between the outer diameter of the jacket tube and the borehole inner wall.
In the following, the invention will be explained in more detail by way of exemplary embodiments schematically illustrated in the accompanying drawing. Therein:
In the illustration according to
A jacket tube, which is generally denoted by 7, follows upon the end of the drill bit 4 facing away from the interior of the borehole, wherein it is apparent that the jacket tube 7 is comprised of a plurality of jacket tube elements telescopically arranged one within the other and denoted in the Figures by 8, 9 and 10, respectively.
As a function of the length of a borehole 2 to be produced as well as the length of the individual jacket tube elements 8 to 10, any number differing from that illustrated in the Figures, of mutually telescopically insertable jacket tube elements can be provided.
While
Subsequently, a curable fluid like, for instance, injection mortar is fed into the free space between the borehole or borehole inner wall 2 and the outer diameter of the respective jacket tube elements 8, 9 and 10, as will be explained in more detail below with reference to
By securing the jacket tube 7 by the aid of the fixing elements 15 as well as tensioning the anchor-forming jacket tube 7, or the individual telescopic jacket tube elements 8, 9 and 10, the proper fixation of the anchor 7 can be ensured. The step-like regions formed between the individual jacket tube elements 8, 9 and 10 in the sense of an enlargement of the outer diameter of the jacket tube 7 in the direction towards the interior of the borehole provide a reliable compaction of the curable fluid introduced into the free space 12, so that a safe adhesion between the outer periphery of the jacket tube 7, or the individual jacket tube elements 8, 9 and 10, and the borehole inner wall 2 will be obtained.
If the anchorage provided by the anchor-forming jacket tube 7 is not sufficient, it is, moreover, indicated in
From the illustration according to
In the enlarged illustration according to
From the schematic illustration according to
It may be envisaged that the supply duct 21, in accordance with the passage openings 23 of the jacket tube 7, or the individual jacket tube sections 8, 9 and 10, comprises a plurality of feed openings 22 and respective sealing elements 24 and 25 in order to enable the substantially simultaneous filling of the free space 12 between the outer periphery of the jacket tube 7 and the borehole inner wall 2 over the entire length of the jacket tube 7.
Alternatively, it is, for instance, possible to provide feed openings 22 radially about the periphery of the supply duct 21 each on the level of the respective passage openings 23 of the jacket tube 7, or individual jacket tube elements 8, 9 and 10, such that the supply duct 21, after the respective filling of partial regions of the free space 12, will be pulled out of the interior of the jacket tube 7 by an appropriate length in order to reach a position substantially in alignment with further passage openings 23 and thereby enable the free space 12 to be progressively filled, whereupon, prior to the final solidification of the curable fluid introduced into the free space 12, another tensioning of the anchor formed by the jacket tube 7 will be effected.
It is apparent that, especially on the end 26 facing the interior of the borehole, the additional anchorage 16, which is, for instance, formed by a profiled solid rod, comprises guide elements 27 to enable the substantially central introduction of the solid rod 16. For a more extensive anchorage during the tensioning of the solid rod 16, it is provided that either the end 26 is engaged or coupled with the drill bit 4 or flap or hook elements, which are schematically indicated at 28 in the region of the guide 27, act against the extraction of the additional anchoring rod 16 in the sense of arrow 29 during tensioning, so that the anchoring effect will be enhanced by said additional anchorage 16.
In order to further increase the anchoring performance, in particular in cooperation with a profiled outer surface of the additional anchoring rod 16, even the annular or hollow space of the jacket tube 7 can be filled with a curable fluid upon introduction of the same.
This is a continuation of PCT/A05/000101 filed Mar. 22, 2005 and published in German.
| Number | Date | Country | Kind |
|---|---|---|---|
| A 509/2004 | Mar 2004 | AT | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/AT05/00104 | Mar 2005 | US |
| Child | 11523669 | Sep 2006 | US |
