1. Technical Field
The present disclosure relates to a method and apparatus for forming pilings and anchors in poor soil and earth conditions.
2. Description of the Related Art
As best illustrated in
The method of forming a pile in the prior art comprises the successive acts of providing anchor 10 comprising shaft 12 having bit 14 at one end of thereof, placing bit 14 in soil, turning shaft 12, and applying pressure to shaft 12 generally in the direction of the major axis of shaft 12 thereby forcing anchor 10 into soil, ground or other substrate 16 (the drilling direction) and thereby forcing soil, ground or other substrate material 16 out of a region 20 surrounding shaft 12. Shaft 12 may be comprised of a plurality of subshafts coupled together by a coupler, 12b (
When anchor 10 is located sufficiently deep within soil, ground or other substrate 16, and when region 20 is filled up with fluid grout until fluid grout fills region 20 such that fluid grout flows out of region 20 and above the surface of soil, ground or other substrate 16, drilling may cease and fluid grout may be permitted to solidify to generally encapsulate anchor 10. Bit 14 is therefore a sacrificial bit in that it is not retrieved from anchor 10 before it is generally encapsulated by the solidified fluid grout. The solidified fluid grout increases the structural integrity of anchor 10 and helps prevent anchor 10 from bending or buckling under compression and increases the structural integrity of anchor 10 within soil, ground or other substrate 16 under both tension and compression.
However, where soil or ground 16 is poor quality (e.g., soft, porous or contains voids), region 20 will not be sufficiently contained or bound. Consequently, in the prior art method described above, fluid grout may traverse away from shaft 12 and may not fill region 20 and may not flow out of region 20 and above the surface of soil, ground or other substrate 16. When this occurs, the structural integrity of anchor 10 under both compression and tension is unknown and compromised. For example, without a generally encapsulating solidified grout, anchor 10 is in a void or in direct contact with poor soil and may be more prone to bending or buckling. Without generally encapsulating anchor 10 with solidified fluid grout, the bond strength of shaft 12 with soil, ground or other substrate 16 may be compromised thus reducing the strength of anchor 10 in compression or tension.
A method for forming pile may be summarized as including providing an anchor comprising a shaft; providing a bit fixed at one end of said shaft; providing a casing about said shaft; releasably coupling said casing to said shaft; placing said anchor in soil; motivating said shaft to advance said anchor into said soil to force said soil out of a region surrounding said shaft; decoupling said casing from said shaft; and continuing to motivate said shaft to continue to provide said anchor into the soil.
The method for forming pile may further include providing a reservoir of a fluid grout; and allowing said fluid grout from said reservoir of fluid grout to flow into said region surrounding said shaft, and allowing said fluid grout to solidify. Allowing said fluid grout from said reservoir of fluid grout to flow into said region surrounding said shaft may include forcing said fluid grout through a tubular passage in said shaft, through an outlet port in said shaft in the region surrounding said shaft. Allowing said fluid grout from said reservoir of fluid grout to flow into said region surrounding said shaft may include forcing said fluid grout through a tubular passage in said shaft and into a cavity in said bit and through an at least one outlet port in said bit in the region surrounding said shaft. Motivating said shaft may include turning said shaft. Motivating said shaft may include applying pressure to said shaft. Said shaft may have a major axis along the length of said shaft and wherein said casing may have a major axis along the length of said casing. Said casing may be provided about said shaft generally coaxial with the major axis of said shaft. Said bit may be adapted to engage said casing to maintain space between said shaft and said casing.
The method for forming pile may further include providing a centralizer disposed between said bit and said casing, said centralizer being adapted to maintain space between said shaft and said casing. Said centralizer may be fixed to said shaft.
A method for forming pile may be summarized as including providing an anchor comprising a shaft having a major axis along a length of said shaft, a bit fixed at one end of said shaft, and a stop releasably coupled to said shaft; providing a casing having a major axis along a length of said casing; disposing said major axis of said casing co-axially with the major axis of said shaft and between said bit and said stop; maintaining a separation between shaft and casing to create a first region between said shaft and said casing; placing said anchor in soil; turning said shaft while applying pressure to said shaft to urge said anchor into said soil thereby forcing a portion of said soil out of a second region surrounding said shaft; decoupling said stop from said shaft; continuing to turn said shaft while continuing to apply pressure to said shaft to continue to urge said anchor into the soil; flowing fluid grout into said second region surrounding said shaft and permitting said fluid grout to flow into said first region between said shaft and said casing; ceasing to turn said shaft and ceasing to apply pressure; and allowing said fluid grout to solidify.
Maintaining a separation between shaft and casing may include providing a centralizer therebetween.
An apparatus to form piles may be summarized as including an anchor comprising a shaft; a casing having a passage therethrough into which at least a portion of the shaft is received to form a region between the portion of the shaft and casing to fluidly receive a fluid grout therethrough, the casing releasably coupled to the shaft at least for translation therewith while coupled; a bit fixed at a distal end of said shaft, the bit having a cavity and at least one outlet port to provide fluid communication between the cavity and an exterior of the bit, the cavity in fluid communication with the region between the portion of the shaft and the casing to fluidly communicate the fluid grout from the region between the portion of the shaft and the casing to the exterior of the bit.
The apparatus to form piles may further include a selectively detachable coupler that selectively detachably couples the casing to the shaft.
The apparatus to form piles may further include a centralizer coupled to the shaft and the casing to maintain a separation therebetween. At least one of the bit or the casing may include a lip that maintains a separation between the shaft and the casing.
The apparatus to form piles may further include a stop disposed at the distal end of the shaft, the stop releasably fixed to the shaft and which prevents a retreat of the casing along the shaft in a direction opposite a direction in which the bit and the shaft advance during drilling.
In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale. For example, the shapes of various elements and angles are not drawn to scale, and some of these elements are arbitrarily enlarged and positioned to improve drawing legibility. Further, the particular shapes of the elements as drawn, are not intended to convey any information regarding the actual shape of the particular elements, and have been solely selected for ease of recognition in the drawings.
In the following description, certain specific details are set forth in order to provide a thorough understanding of various disclosed embodiments. However, one skilled in the relevant art will recognize that embodiments may be practiced without one or more of these specific details, or with other methods, components, materials, etc. In other instances, well-known structures associated with pilings such as pile drivers, motors, compressors, etc., and methods for installing pilings have not been shown or described in detail to avoid unnecessarily obscuring descriptions of the embodiments.
Unless the context requires otherwise, throughout the specification and claims which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense, that is as “including, but not limited to.”
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.
The headings and Abstract of the Disclosure provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
Anchor 10 is rotated about its major axis and pressure is applied along the major axis to advance or urge the anchor into soil, ground or other substrate 16.
Anchor 10 may continue to be drilled into soil, ground or other substrate 16b. Soil, ground or other substrate 16b may be of a preferred quality over soil, ground or other substrate 16 in that it may be less porous, or contain fewer voids. Region 20b in soil, ground or other substrate 16b may sufficiently bound such that fluid grout flowed from bit 14 may not traverse out of region 20b, but rather flow up through casing 24 which has remained in place after stop 22 was disengaged from shaft 12. Once anchor 10 achieves its desired depth, fluid grout may continue to be flowed until fluid grout reaches the surface of soil, ground or other substrate 16 after which fluid grout may be allowed to solidify and substantially encase anchor 10.
Centralizer 28 may protect casing 24 from bit 14 which is aggressively rotating and hammering. That is, centralizer 28 may prevent contact between the rotating and hammering bit 14 and casing 24. This may be particularly advantageous where casing is made of a material such as PVC or plastic pipe that may be damaged if placed into contact with the rotating and hammering bit 14. Centralizer 28 may also help prevent casing 24 from being contaminated or plugged with unwanted materials during its installation in the method described herein, until such time as stop 22 is disengaged and centralizer 28 separates from casing 24 under influence from coupler 12b. Centralizer 28 also maintains separation between casing 24 and shaft 12 and helps to achieve uniformity in the encapsulation of shaft 12 with fluid grout.
In one embodiment, anchor 10 may be motivated into soil, ground or other substrate 16 with water as the flushing medium to assist in the flushing of soil, ground or other substrate material from a region around shaft 12. Stop 22 may be released from shaft 12 and centralizer 28 may be disengaged from the casing 24 by coupler 12. At that time fluid grout may be pumped through shaft 12 via the hollow interior 12a to bit 14 where it is motivated to the region surrounding bit 14 via ports 14a. Fluid grout may then naturally follow the path of least resistance which is through the space, region or volume between casing 24 and shaft 12 to the surface.
In another embodiment, bit 14 may be adapted with a lip or series of protrusions or other registration elements which may fit within or outside casing 22, or both to ensure that casing 24 is maintained generally coaxial with shaft 12 to, replace the function of centralizer 28.
In another embodiment, casing 24 may be adapted with a lip or series of protrusions or other registration elements which may fit within or outside bit 14, or both to ensure that casing 24 is maintained generally coaxial with shaft 12, to replace the function of centralizer 28.
In another embodiment, casing 24 may be adapted to be releasably coupled to shaft 12 in place of stop 22.
In another embodiment, shaft 12 may be adapted to be releasably coupled to casing 24 in place of stop 22.
Anchor 10 may be of a form provided by Contech Systems Ltd. of 8150 River Road, Delta British Columbia, Canada. Shaft 12 may be comprised of plastic, metal or other material suitable to a person of ordinary skill in the art for a particular application. Shaft 12 may comprise a single element or may be comprised of multiple lengths of shaft coupled together via coupler 12b. Coupler 12b may constitute a protrusion along shaft 12 and may serve to cause centralizer 28 to be separated from casing 24 after casing 24 has been decoupled from shaft 12 via the release of stop 22 and decoupling of stop 22 from shaft 12, as seen in
Pressure and turning applied to anchor 10 to promote, advance or urge anchor 10 into soil, ground or other substrate may be continuous or may be in a rotary or rotary percussion like fashion as is known to a person of ordinary skill in the art.
Casing 24 may be made of plastic, metal or other material suitable to a person of ordinary skill in the art for a particular application. Casing 24 may be comprised of a single element or may be comprised of multiple lengths of casing coupled together in a manner known by a person of ordinary skill in the art, depending on the nature of the material used for casing 24. Casing 24 is shown in the Figures as a single element but the Figures should not be interpreted as limiting the generality of the disclosure.
The above description of illustrated embodiments, including what is described in the Abstract, is not intended to be exhaustive or to limit the embodiments to the precise forms disclosed. Although specific embodiments of and examples are described herein for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the disclosure, as will be recognized by those skilled in the relevant art. The teachings provided herein of the various embodiments can be applied to other apparatus for forming pilings and method of forming pilings, not necessarily the exemplary methods and apparatus generally described above. For example, the various embodiments described above can be combined to provide further embodiments.
These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.
This application claims benefit under 35 U.S.C. 119(e) of U.S. Provisional Patent Application Ser. No. 61/505,266, filed Jul. 7, 2011, which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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61505266 | Jul 2011 | US |