US20230089034A1

US20230089034A1 - Novel system and method for installing grout-filled friction piles

Info

Publication number: US20230089034A1
Application number: US17/481,868
Authority: US
Inventors: Michael Karantinidis
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-09-22
Filing date: 2021-09-22
Publication date: 2023-03-23

Abstract

The friction pile system may include a steel pipe column, an auger spiraled around its exterior surface, a helical plate near the tip, and small structural elements located around the helix. A plurality of perforations may be provided on the pipe wall. The method of installation includes screwing the pipe assembly down into the ground by rotating it with a drivehead and simultaneously pressure injecting cement grout inside the pipe. The structural elements including weld beads maintain the bore hole created by the rotating helix and also guide grout to flow out though the perforations and upward along the auger while spreading outward filling in the hole. Thus the engineered pipe assembly leverages the mechanical energy of drilling to pressurize grout upward and outward improving bond with soil yielding high pile capacity.

Description

FIELD

The present technology is generally related to structural piles, pile driving techniques, and more particularly to friction piles and methods of installing friction piles.

BACKGROUND

Timber piles and standard steel H-piles are well known structural load-bearing piles in the construction industry. These piles are driven into the ground by impacting their head with a falling weight or a driver. The impact vibrates the ground and, through it, the near-by structures, thus creating a potential for adverse effects and/or damage. Therefore, in a crowded metropolitan area, the impact-driven H-piles and timber piles may not be the most suitable pile of choice. Another group of piles is available in the construction industry that are drilled, rather than impact-driven, into the ground thus avoiding and/or reducing the risk of damaging near-by structures. Caisson piles, micro (or mini) piles and helical piles belong to this group of drilled piles. For caisson and micropiles, a cylindrical steel casing with drilling teeth at the tip is inserted into the ground by a rotary drilling machine and the soil inside the casing is removed either by injecting water or by air pressure. Caisson piles transfer load to bedrock by cutting a socket into it. Cement grout may fill in both the steel casing and the socket in the bedrock, and reinforcing steel rods may be inserted in the grout to make the pile stronger. Micropiles, on the other hand, transfer load to competent soil strata through which they pass. This is achieved in conventional micropiles by lifting up the steel casing gradually and filling in the void left by the casing with cement grout thus forming a bond between the grout column and the surrounding soil in the competent layers. Reinforcing steel rods may be inserted into the grout column of a micropile to make the pile stronger. In contrast to caisson piles or micropiles, helical piles use a steel pipe and one or more helical plates near the bottom. The helices facilitate screwing the pipe in the ground by a rotary drive head. The helical plates may also act as load transferring structural elements because they bear on soil. In the construction industry, caisson piles, micropiles and helical piles may be called by different names and may use installation techniques slightly different from those described above. In any event, whereas the larger-diameter steel casing of the caisson piles and micropiles provides a means for drilling and pouring a cement grout column with reinforcing steel that together carries the structural load, the steel pipe of conventional helical piles is relatively narrow and is the sole means for carrying the load down from the structure above - thus limiting the pile load transfer capacity. On the other hand, both caisson piles and conventional micropiles may require heavier machines and more extensive operations making them less economically attractive than helical piles. Accordingly, there is a need for the design of a new pile system that takes advantage of the relative ease of installation of helical piles and, at the same time, delivers the ruggedness of a grout column for effective load transfer by friction. If the body of a conventional helical pile is selected, at least one challenge would be how to fill in the hole created by the helix with grout before soil caves into it. For example, merely letting grout trickle down by gravity subjects the conventional helical pile to risk of formation of an unreliable, nonuniform grout column. What is needed is a system and a method that ensures grout column quality while maintaining low costs.

SUMMARY

The techniques of this disclosure generally relate to a new design of the micropile and a novel method of installation.
In one aspect, the new micropile, hereinafter called friction pile system, may include a hollow column having an interior comprising a centrally disposed longitudinal axis extending in a longitudinal direction from a driving end to a closed end, the column having an outside surface, an inside surface, and a first width extending in a lateral direction perpendicular to the longitudinal direction, for example. In various embodiments, an auger portion may be disposed on the outside surface of the column and include a first helical pattern fanning out in the lateral direction. A pressed, bent steel plate mounted near the tip of the pipe column may form the second helical pattern. In various embodiments, a plurality of steel brackets and weld beads are strategically located around the second helical plate. In various embodiments, a plurality of perforations may be selectively disposed along the column and penetrating the outside surface and inside surface respectively. The perforations may be configured to provide a passageway for supplying cementitious material from the interior of the column through the outside surface as excreted cementitious material, for example. In various embodiments, the brackets and the auger portion may be configured to convey the excreted cementitious material towards the top end upon rotation of the column around the longitudinal axis.
In another aspect, the disclosure provides for a method of installing the friction pile system. The method may include screwing down the pipe assembly into the ground by using the bottom helix, for example. In various embodiments, the method may include the step of injecting cementitious material under pressure into an interior of the column through an upper end of the hollow column, for example. In various embodiments, the method may further include the step of excreting the cementitious material from the interior of the column through at least the first perforation, for example. In various embodiments, the method may include the steps of guiding the excreted cementitious material with steel brackets and conveying it upward along the auger portion from the lower elevation of the rotating pipe assembly to the upper elevation, for example.
The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an elevation view of an example engineered pipe assembly and the novel friction pile.

FIG. 2A is an enlarged view of the drilling and grout injecting portion of the friction pile of FIG. 1 , rotated by 90 degrees.

FIG. 2B is a section view taken along line C₁-C₁of FIG. 1 .

FIG. 3A is a section view taken along line C₂-C₂of FIG. 1 .

FIG. 3B is an alternate view of FIG. 3A viewed from a rotated perspective of about 90 degrees.

FIG. 4 is an example flow chart of a method of installing an example novel friction pile system.

DETAILED DESCRIPTION OF PILE

The following discussion omits or only briefly describes certain components, features and functionality related to one type of friction piles also called micropiles and related methods of installing these friction piles, which are apparent to those of ordinary skill in the art. It is noted that various embodiments are described in detail with reference to the drawings, in which like reference numerals represent like parts and assemblies throughout the several views, where possible. Reference to various embodiments does not limit the scope of the claims appended hereto because the embodiments are examples of the inventive concepts described herein. Any example(s) set forth in this specification are intended to be non-limiting and set forth some of the many possible embodiments applicable to the appended claims. The particular features described herein can be used in combination with other described features in each of the various possible combinations and permutations unless the context clearly indicates otherwise.
Referring generally to FIGS. 1-3B an example friction pile 110 (also referred to as a friction pile system 110) is disclosed. Friction pile 110 includes steel pipe assembly 100 and a cement grout column around it. In various embodiments, the pipe assembly 100 may include a body 10, e.g., a hollow cylindrical column and/or steel pipe. The body 10 may extend in a longitudinal direction (represented by Y direction in the labeled coordinate system) and include an outside surface and an inside surface defining an interior void space therein. In various embodiments, the interior void space may be filled with a cementitious material, such as, e.g., a flowable grout or the like. Filling the interior void space of the body 10 with a cementitious material, may provide additional bearing strength and/or structural benefits as will be explained in further detail below.
The interior void space may define a centrally disposed longitudinal axis L-A extending in the longitudinal direction from a top end 101 to a bottom end 102. The top end 101 of body 10 may be configured for connecting to a rotary driver machine configured to rotate the pipe assembly 100, for example. Additionally, the top end 101 may comprise an open end, or at least a partially open end granting access to the interior void space of the body 10. A bottom-most surface of the bottom end 102 may comprise a closed end preventing access to the interior void space of the body 10 (or at least a substantially closed end). The body 10 may have a width that extends in a lateral direction (represented by X direction in the labeled coordinate system) through the body 10 and passing through the longitudinal axis L-A. The width of body 10 may be any size depending on the particular structural load bearing requirements. In various embodiments, the longitudinal direction and lateral direction may be perpendicular to one another.
The bottom end 102 may include a capping portion 16, for example. In various embodiments, the capping portion 16 comprises a steel plate having a planar outside surface that is welded to the bottom-most surface of the body 10, e.g., a continuous fillet weld, etc. that is suitable for the thickness of the steel plate and body 10. Additionally, the capping portion 16 may be flush with the outside surface of the body 10. Furthermore, the capping portion 16 may be angled with respect to the body 10 and/or longitudinal axis L-A at about 25 degrees to about 65 degrees, about 35 degrees to about 55 degrees, or in some embodiments about 45 degrees, terminating in a peak that extends from the body 10 in the direction of the longitudinal dimension. The capping portion 16 may be configured to loosen and/or scratch the ground and push debris laterally to the side while the pipe assembly 100 is being rotated. In some embodiments, (not illustrated) a boring machine may initially drive a relatively narrow pilot hole for guiding the cutting portion 16 into the ground; although, in other embodiments a pilot hole is not necessary.
In various embodiments, a helix portion 12 may be disposed adjacent the capping portion 16 proximate the bottom portion 102. The helix portion 12 may be disposed on the outside surface of the body 10 and have a geometry that is defined by a first helical pattern fanning out from the body 10 in the lateral direction. For example, the first helical pattern may spiral along the outside surface of the body 10 and have about a 4 inch to 8 inch pitch, and in some embodiments about a 6 inch pitch. In the illustrated embodiment, the helix portion 12 makes about one full revolution about the outside surface of body 10 although in other embodiments the helix portion 12 may be repeated with additional plates and/or make additional revolutions around body 10. In various embodiments, the helix portion 12 may be welded to the outside surface of body 10 by, e.g., a thick and continuous fillet weld of about ¼ an inch (quarter of an inch) to about ½ an inch (half of an inch). Additionally, and when viewed as a section cut in plan view (see FIG. 2B), the helix portion 12 may widen the overall width of the pipe assembly 100 to about 10 inches to about 16 inches in width and more particularly about 14 inches in width.
Pipe assembly 100 may further include an auger portion 14 disposed on the outside surface of the body 10 that spirals upward along the body 10 between the helix portion 12 and the top end 101. In some embodiments, the auger portion 14 may begin at an elevation that is proximate to the upper most portion of the helix portion 12, for example. In other embodiments, the auger portion 14 may begin at an elevation that is farther away from helix portion 12 and in other embodiments still auger portion 14 may terminate and/or pick up where helix portion 12 terminates. Auger portion 14 may have a geometry that is defined by a second helical pattern fanning out from the body 10 in the lateral direction. The second helical pattern may be different than the first helical pattern. For example, the auger portion 14 may spiral along the outside surface of the body 10 and have about a 8 inch to 16 inch pitch or in some embodiments about a 12 inch pitch. In at least one embodiment, the pitch of the auger portion 14 is about twice that of the helix portion 12. The auger portion 14 may spiral along the outside of the body 10 from an elevation proximate the helix portion 12 to the top end 101. The auger portion 14 may be formed by cutting from a wide steel plate, bending it according to the design criteria, and welding it the outside surface of body 10.
Auger portion 14 may further be functionally supported by a plurality of angles and/or other structural elements 18. Structural elements 18 may comprise a closed L-shaped gusset or flange or a V-shaped gusset or a flange that is disposed on the outside surface of the body 10. For example, both outside surfaces of a 90 degree L-shaped gusset may face away from body 10 and the inside surfaces that form a 90 degree bend face the outside surface of body 10. For example still, the outside notch of the L-shaped gusset may point away from body 10 as illustrated in FIG. 2B. With reference to FIG. 1 , in various embodiments at least one structural element 18 (L-shaped gusset, V-shaped gusset, flange, etc.) may extend in the longitudinal direction along an outside surface of body 10 from an intermediate upper surface of auger portion 14 to an intermediate lower surface of auger portion 14. The top and bottom of each structural element 18 may be angled to conform to the pitch of auger portion 14. Additionally, each surface of structural element 18 that contacts body 10 and/or auger portion 14 may be welded to the corresponding structure according to the same and/or similar techniques as described above. During installation, the structural elements 18 may push the soil away and keep the hole temporarily open, for example. Structural elements 18 may have other advantages as will be explained in further detail below.
Pipe assembly 100 may further include at least one perforation 19. In the example embodiment, pipe assembly 100 may include a plurality of perforations 19 selectively disposed along the body 10 at discrete locations. Each perforation 19 may penetrate the outside surface and inside surface of body 10. In various embodiments, perforations 19 may take any suitable shape, e.g., a circular hole (weep hole), an oblong hole, a slit extending in the longitudinal direction, a slit extending in the lateral direction, and/or an angled slit extending in a direction that is angled with respect to the longitudinal direction. In the embodiment of FIG. 1 , a first perforation 19 a is provided at an elevation corresponding to a tip of capping portion 16, e.g., first perforation 19 a is proximate the tip of capping portion 16. In the illustrated embodiment, the first perforation 19 a extends through the outside surface and inside surface of body 10, rather than the above described steel plate forming the closed end 102. Additionally, in various embodiments the first perforation 19 a may be disposed below helix portion 12, for example. With reference to FIG. 2A, a second perforation 19 b may be disposed at an elevation corresponding to an upper terminal end of helix portion 12. In some embodiments, the first perforation 19 a (lower perforation) and second perforation 19 b may be vertically aligned with one another in the longitudinal direction. In other embodiments, the first and second perforations 19 a, 19 b may be offset from one another. Additionally, in various embodiments, a structural element 13 such as a weld seam or bead may surround the perimeter, or a portion thereof, of the perforations 19 a, 19 b. For example, first perforation 19 a may have a circular bead or weld seam that completely surrounds a circular weep hole and second perforation 19 b may have a V-shaped or an L-shaped bead that partially surrounds a circular weep hole. In each of these examples, the bead or weld seam is configured to protect the perforations 19 a, 19 b from collapsing soil.-Those with skill in the art will appreciate that the type of structural element 13 may depend on the location of perforations 19 with respect to the adjacent structure. For example, perforation 19 b is protected by an L-shaped structural element 13 fanning out from an adjoining weld seam of an uppermost terminal end of helix portion 12.
In various embodiments, perforations 19 may be configured to provide a passageway for supplying cementitious material from the interior of the body 10 through the outside surface of body 10 as excreted cementitious material. For example, cementitious material may be injected into the interior of body 10 at the top end 101 by any known means such as a swivel system. In some embodiments, cementitious material such as a flowable grout may be injected into the interior of body 10 under pressure, also referred to in the art as pressure injection grouting. The pressure applied may be in the range of 50-200 psi and substantially constant as the pipe assembly 100 is drilled further into the ground. In turn, the interior of the body 10 may become filled with cementitious material and the cementitious material may flow from the interior of the body 10 through the perforations 19 and to the outside of the body 10. The cementitious material may flow to the outside of the body 10 due to gravity forces initially and then being pressure injected.
In some embodiments, the cementitious material may be injected into the interior of the body 10 while the pipe assembly 100 is being inserted into the ground by rotation. For example, at least a portion of the rotation and insertion of the pipe assembly 100 and the pressure injection grouting may be performed simultaneously. In some embodiments, cementitious material may continue to be injected into the interior of body 10 after pipe assembly 100 has reached some or the entirety of the target depth. In other embodiments, the cementitious material may be injected in whole or in part after the pipe assembly 100 has been drilled into the ground and reached its target depth. In various embodiments, a target depth may correspond to an elevation where the depth through the competent soil layer is considered sufficient for the design pile capacity, for example. In some embodiments, the pipe assembly may reach the bedrock.
Consistent with the disclosure herein, the excreted cementitious material will surround the outside of the body 10 due to flowing through penetrations 19, for example. The cementitious material will initially flow through a perforation 19 at the lowest elevation and thereafter will flow through perforations 19 at higher elevations until the cementitious material fills the interior of body 10 and the surrounding space around the pipe assembly 100, i.e. the bore hole and void spaces in the surrounding ground. In various embodiments, perforations 19 may be disposed along the outside of body 10 at regularly spaced elevations from the closed bottom end 102 to the top end 101 or the perforations 19 may be selectively disposed along the outside of body 10 at various elevations configured to facilitate the dispersal of the cementitious material around the body 10. For example, FIG. 2A is an enlarged view of the capping portion 16 and helix portion 12 of pipe assembly 100. As illustrated, perforation 19 a is disposed beneath the helix portion 12 and facilitates the placement of cementitious material beneath helix portion 12. Perforation 19 b is selectively placed at an elevation where the cementitious material will be ejected above the lower flange of helix portion 12. This location facilitates the conveyance of cementitious material on the outside of body 10 and helix portion 12 upwards towards the top end. For example, by rotating pipe assembly 100 the ejected cementitious material on the outside of body 10 is conveyed upward by the helix portion 12 and thereafter is conveyed upward towards the top end 101 by the auger portion 14.
This arrangement is particularly advantageous because gravity fed grout may be insufficient, on its own, to force the cementitious material through perforations 19 and upwards to fill the whole cavity (bore hole) surrounding the pipe assembly 100. Notably, embodiments in accordance with the pressurization principles of this disclosure provide a plurality of selectively disposed perforations 19 that feed cementitious material to the helix portion 12 and auger portion 14 such that the helical pattern 11, including the helix portion 12 and auger portion 14, conveys the excreted cementitious material upwards and facilitates even dispersal of the cementitious material around the outside of body 10.
FIG. 2B is a section view taken along line C₁-C₁of FIG. 1 . In the example illustration, it is shown that body 10 may include various structural reinforcing elements 18 and 20. As explained in further detail above, structural element 18 may comprise an L-shaped bracket having a first outside surface 18 a and a second outside surface 18 b that face away from body 10. In the example embodiment, this section of pile assembly 100 includes two oppositely and symmetrically disposed structural element(s) 18 with each having an interior angle of about 90 degrees. Additionally, in various embodiments an additional V-shaped structural element 20 may be secured to at least one of the L-shaped structural element(s) 18. For example, the V-shaped structural element 20 may include a first outside surface 20 a and a second outside surface 20 b forming an interior angle therebetween of about 45 degrees. The V-shaped structural element 20 may be secured to the L-shaped structural element 18 by welding an edge of first surface 20 a to one of the two outside surfaces of the L-shaped structural element(s) 18 and welding an edge of second surface 20 a to the other outside surface of the L-shaped structural element 18. In the illustrated configuration, the second surface 20 b may be substantially co-planar with the corresponding surface of L-shaped structural element 18. For example, the second surface 20 b may not be exactly coplanar, although it may include a planar outside surface that extends in a direction that is substantially parallel with the corresponding planar outside surface of L-shaped structural element 18. This geometrical configuration is also particularly advantageous for pushing ejected cementitious material laterally away from body portion 10. For example, the structural elements 18 and 20 are configured to push the excreted cementitious material away from the outside surface of body 10 when pipe assembly 100 is being rotated. This facilitates the dispersion of the cementitious material in the bore hole, and also provides positive pressure forcing the cementitious material into the surrounding ground and/or strata under pressure.
In this way, embodiments in accordance with the principles of this disclosure provide for a pipe assembly 100 that is configured to convey cementitious material vertically along the outside of body 10 in the longitudinal direction and force cementitious material into the available pore space in the surrounding soil or strata. The pipe assembly 100 is engineered in a way that the mechanical energy of drilling the pipe downward will be leveraged to guide and push the grout upward along the auger to fill the bore hole. For example, the rotation of pipe assembly 100 may guide and push the grout upward along the auger 14 to fill the bore hole. In addition to assisting upward movement of grout, the external pressure will push the grout laterally outward thereby penetrating soil and improving a bond between the soil and grout column. This configuration facilitates the even dispersal of the cementitious material throughout the inside of body 10 and throughout the outside of body 10. Once the pipe assembly 100 has been drilled to a sufficient depth, and the interior of the body 10 will not receive any more cementitious material, rotation of the pipe assembly 100 may be stopped and the cementitious material may be allowed to cure and/or harden. Because the cementitious material is substantially homogenously dispersed on the outside of body 10, in the interior of body 10, and is forced into the surrounding ground at pressure, the disclosed friction pile system 110 provides for a strong load bearing system in both the vertical direction and in the lateral direction in a cost effective manner.
In some embodiments, it is impractical to provide a single pipe assembly 100 of a length that can reach a target design depth. Accordingly, multiple pipe assemblies 100 that are the same as, substantially the same as, and/or similar to pipe assembly 100 may be connected together at a construction site to provide for a final friction pile system 110 having an appropriate length to reach a target design depth. For example, multiple pipe assemblies 100 may be “spliced” together. FIG. 3A is a section view taken along line C₂-C₂of FIG. 1 . In the example embodiment, a first body portion 10 a is securely coupled to a second body portion 10 b. This procedure may be referred to as splicing in the construction industry. FIG. 3B is an alternate view of FIG. 3A viewed from a rotated perspective of about 90 degrees. In the example embodiment, an upper portion of first body 10 a and a lower portion of second body 10 b are each covered by a collar 22 such as a pipe sleeve having an interior surface and geometry that corresponds to the curvature of the outside surfaces of first body 10 a and second body 10 b, for example. Collar 22 may surround the outside surfaces of first body 10 a and second body 10 b at the relevant splicing area. The first body 10 a and collar 22 may each be connected by at least one anchor bolt 24. In one embodiment the anchor bolt 24 may have a cross sectional diameter of 1 inch. In various embodiments, the anchor bolt 24 may extend through a lower portion of collar 22 and an upper end of column 10 a. The anchor bolt may be securely tightened and provide compression of collar 22 against the outside surfaces of first body 10 a and second body 10 b. In various embodiments, collar 22 may be welded to body 10 b with a relatively thick and continuous weld according to the same or similar techniques as explained above. In some embodiments, collar 22 may be additionally connected to body 10 b by plug weld 23. In this way, the collar 22 functions as a coupling element that securely attaches first body 10 a to the second body 10 b.
FIG. 4 is an example flow chart of a method 200 of installing an example novel pressurized friction pile system, e.g., friction pile system 110. Although the method of installation is described in the context of friction pile system 110, the method is not limited to solely the applicability of friction pile system 110. At step 202, a pipe assembly 100 having structural and functional characteristics consistent with the above disclosure may be provided. The pipe assembly provided at step 202 may be inserted into the ground by rotating it about the longitudinal axis by a rotary machine, for example. For example, the helix system 11 and auger 14 of FIG. 1 may create a bore hole and push soil and surrounding strata out as the pipe assembly rotates. At step 204, as pipe assembly 100 is screwed into the ground, cementitious material may be injected into an interior of the pile assembly. The cementitious material may be pressure injected or gravity fed and may comprise a flowable material such as grout. In some instances, the step of injecting grout into pile assembly 100 may be considered the operative step with which pipe assembly 100 may be referred to as a micro-pile, minipile, and or friction pile, for example. At step 206, the cementitious material may be excreted from the interior of the pipe assembly 100 to the outside of the pipe assembly 100. For example, the cementitious material may be excreted through perforations in the sidewalls of the pipe assembly 100. At step 208, the excreted cementitious material may be conveyed upwards along the outside surface of the pipe assembly 100. For example, the auger pattern on the surface may convey the excreted grout upwards due to the rotation of the pipe assembly 100 being performed as described at step 202. Additionally, at step 210, the excreted cementitious material may be pushed away from an outside surface of the friction pile in the lateral direction. For example, any one of the structural elements, L-shaped brackets, V-shaped brackets may push or sweep the excreted cementitious material out laterally away from the friction pile and facilitate the dispersion of the excreted cementitious material in the boring hole of which the pipe assembly 100 is disposed in and/or has created. Those with skill in the art will recognize that in at least some embodiments, steps 202, 204, 206, 208, and/or 210 may be performed at the same time. At step 212, rotation of the pipe assembly and injection of grout may be stopped when the design depth has been reached. In some embodiments, injection of grout may continue after the design depth has been reached to ensure that an adequate grout column is formed. Furthermore, additional pipe sections may be joined together with the lead section as necessary to reach the design depth as explained previously. At step 214, the cementitious material inside of the friction pile and the cementitious material outside of the friction pile may be allowed to cure and harden. Additionally, in some embodiments, at least a portion of step 202, step 204, step 206, step 208 and/or step 210 may be performed simultaneously as additional pipe sections are added at step 212. A novel grouted friction pile, also may be called a minipile or micropile, may be completed at step 216.
It should be understood that various aspects disclosed herein may be combined in different combinations than the combinations specifically presented in the description and accompanying drawings. For example, features, functionality, and components from one embodiment may be combined with another embodiment and vice versa unless the context clearly indicates otherwise. Similarly, features, functionality, and components may be omitted unless the context clearly indicates otherwise. It should also be understood that, depending on the example, certain acts or events of any of the processes or methods described herein may be performed in a different sequence, may be added, merged, or left out altogether (e.g., all described acts or events may not be necessary to carry out the techniques).
Unless otherwise specifically defined herein, all terms are to be given their broadest possible interpretation including meanings implied from the specification as well as meanings understood by those skilled in the art and/or as defined in dictionaries, treatises, etc. It must also be noted that, as used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless otherwise specified, and that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.

Claims

What is claimed is:

1. A novel grout-filled friction pile system, comprising:

a hollow column having an interior comprising a centrally disposed longitudinal axis extending in a longitudinal direction from a driving end to a closed end, the column having an outside surface, an inside surface, and a first width extending in a lateral direction perpendicular to the longitudinal direction;

an auger portion disposed on the outside surface of the column and comprising a first helical pattern fanning out in the lateral direction, the auger portion extending in the longitudinal direction along the outside surface of the column towards the top end; and

a plurality of perforations selectively disposed along the column and penetrating the outside surface and inside surface, the plurality of perforations configured to provide a passageway for supplying cementitious material from the interior of the column through the outside surface as excreted cementitious material,

wherein the auger portion is configured to convey the excreted cementitious material towards the top end upon rotation of the column around the longitudinal axis.

2. The friction pile system of claim 1, further comprising a capping portion disposed at a tip of the driving end and including a surface that substantially closes the driving end.

3. The friction pile system of claim 2, comprising:

a helix portion disposed on the outside surface of the column proximate the driving end and comprising a second helical pattern configured to drill the column downward into the ground upon rotation of the column around the longitudinal axis, and

wherein the auger portion is disposed at an elevation that is above the helix portion.

4. The friction pile system of claim 3, wherein an outside edge of the helix portion extends a first distance from the outside surface of the column in the lateral direction and an outside edge of the auger portion extends a second distance from the outside surface of the column in the lateral direction, the first distance being greater than the second distance.

5. The friction pile system of claim 3, wherein the auger portion comprises a first pitch and the helical portion comprises a second pitch, the first pitch being greater than the second pitch.

6. The friction pile system of claim 5, wherein the first pitch is about twice that of the second pitch.

7. The friction pile system of claim 1, further comprising a plurality of structural elements disposed on the outside surface of the column,

wherein at least one structural element of the plurality of structural elements is disposed proximate a corresponding perforation of the plurality of perforations, and

wherein at least one structural element of the plurality of structural elements is configured to push the excreted cementitious material away from the outside surface of the column during rotation of the column.

8. The friction pile system of claim 1, further comprising a plurality of structural elements disposed on the outside surface of the column, at least one structural element of the plurality of structural elements is disposed proximate a corresponding perforation of the plurality of perforations and configured to protect the perforation during rotation of the column.

9. The friction pile system of claim 8, further comprising:

wherein the plurality of perforations includes a first perforation disposed proximate the helix portion.

10. The friction pile system of claim 9, wherein the first perforation comprises a reinforced weep hole.

11. The friction pile system of claim 1, wherein the interior of the column is configured to be substantially filled with the cementitious material.

12. The friction pile system of claim 11, wherein the outside of the column is configured to be substantially surrounded by the conveyed excreted cementitious material.

13. The friction pile system of claim 1, further comprising a plurality of reinforcement angles disposed on the outside surface, each reinforcement angle of the plurality of reinforcement angles extending in the longitudinal direction between a corresponding top surface of the helix pattern to a corresponding bottom surface of the auger pattern.

14. The friction pile system of claim 13, wherein each reinforcement angle of the plurality of reinforcement angles extends laterally from the outside surface in the lateral direction.

15. A method for installing a friction pile system, comprising:

providing a pipe assembly system, comprising:

a hollow column extending in a longitudinal direction and having a substantially closed end, the column defining a centrally disposed longitudinal axis extending in the longitudinal direction, the column including an outside surface and an inside surface,

a helix portion and an auger portion extending along the outside surface of the column from a lower elevation of the column to an upper elevation of the column, and

a plurality of perforations, the plurality of perforations including a first perforation disposed proximate the lower elevation of the column and penetrating the outside surface and inside surface of the column,

injecting cementitious material under pressure into an interior of the column through an upper end of the hollow column;

excreting the cementitious material from the interior of the column through the first perforation;

rotating the pipe assembly system; and

conveying the excreted cementitious material along the auger portion from the lower elevation to the upper elevation.

16. The method of claim 15, wherein: the friction pile system further comprises a plurality of V-shaped gussets disposed on the outside surface of the column and extending laterally from the outside surface of the column, each V-shaped gusset being disposed proximate an elevation of a corresponding perforation of the plurality of perforations.

17. The method of claim 16, further comprising:

pushing the excreted cementitious material away from the outside surface of the column via the plurality of v-shaped gussets, and

wherein at least a portion or an entirety of each of the rotating step, the grout injecting step, the conveying step, and the pushing step is performed simultaneously.