Abstract:
A pile is disclosed for insertion by a pile driver. The pile incorporates transversely extending anchors for increased pull-out resistance.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 61/782,178, filed Mar. 14, 2013, entitled PULL-OUT RESISTANT PILES, the entire disclosure of which is hereby expressly incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to piles. More particularly, the present disclosure relates to piles having anchors for increased pull-out resistance, and to a method for using the same. 
     BACKGROUND OF THE DISCLOSURE 
     Piles are used to transfer a structural load to the soil below the ground surface. Piles may driven into the soil using a vibratory pile driver, for example. Vibratory pile drivers include a large, heavy housing clamped to the upper end of the pile to be driven. The housing may be provided with at least two eccentric weights. The eccentric weights are rotated at high speed to vibrate the housing. The vibration of the housing, coupled with the weight of the housing, causes the pile to sink into the soil below the ground surface. In alternative configurations, the articulated boom of an excavator may be used to drive the pile downward into the soil as it vibrates. Piles may also be impacted or otherwise driven into the soil. 
     SUMMARY 
     The present disclosure provides a pile adapted for insertion by a pile driver. The pile of the present disclosure incorporates transversely extending anchors for increased pull-out resistance. 
     According to an embodiment of the present disclosure, a pile is provided having an upper end, a lower end, and a longitudinal axis that extends between the upper end and the lower end, a longitudinal plane intersecting and extending parallel to the longitudinal axis. The pile includes a first longitudinal wall located on a first side of the longitudinal plane, a second longitudinal wall located on a second side of the longitudinal plane, an interior space formed between the first and second longitudinal walls, and at least one anchor located at least partially in the interior space between the first and second longitudinal walls, the anchor extending transversely to the longitudinal axis. 
     According to another embodiment of the present disclosure, a pile is provided having an upper end, a lower end, and a longitudinal axis that extends between the upper end and the lower end, a longitudinal plane intersecting and extending parallel to the longitudinal axis, a perpendicular plane extending perpendicular to the longitudinal axis. The pile includes a first longitudinal wall located on a first side of the longitudinal plane, a second longitudinal wall located on a second side of the longitudinal plane, an interior space formed between the first and second longitudinal walls, the interior space having a total area measured in a direction perpendicular to the longitudinal axis, and at least one anchor in the interior space, the at least one anchor having a projected area on the perpendicular plane, the projected area of the at least one anchor comprising a majority of the total area of the interior space. 
     According to yet another embodiment of the present disclosure, a method is provided for driving a pile into soil beneath a ground surface. The method includes the steps of coupling a pile driver to a pile, the pile having an upper end, a lower end, a longitudinal axis that extends between the upper end and the lower end, and at least one anchor that extends from the pile in a direction transverse to the longitudinal axis, and driving the lower end of the pile into soil with the pile driver. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is an elevational view of an exemplary pile of the present disclosure shown coupled to a vibratory pile driver before being inserted into the soil; 
         FIG. 2A  is another elevational view showing the pile of  FIG. 1  being vibrated by the vibratory pile driver and driven into the soil; 
         FIG. 2B  is an elevational cross-sectional view of a lower portion of the pile of  FIG. 2A ; 
         FIG. 3  is an elevational cross-sectional view of a lower portion of the pile of  FIG. 1 , which is circled in  FIG. 1 ; 
         FIG. 4  is a plan cross-sectional view of the pile of  FIG. 3 , taken along line  4 - 4  of  FIG. 3 ; 
         FIG. 5  is an elevational cross-sectional view of a lower portion of another exemplary pile of the present disclosure; 
         FIG. 6  is a plan cross-sectional view of the pile of  FIG. 5 , taken along line  6 - 6  of  FIG. 5 ; 
         FIG. 7  is an elevational view of a lower portion of yet another exemplary pile of the present disclosure; 
         FIG. 8  is a plan cross-sectional view of the pile of  FIG. 7 , taken along line  8 - 8  of  FIG. 7 ; 
         FIG. 9  is an elevational view of a lower portion of still yet another exemplary pile of the present disclosure; 
         FIG. 10  is a plan cross-sectional view of the pile of  FIG. 9 , taken along line  10 - 10  of  FIG. 9 ; and 
         FIG. 11  is an elevational view of the pile of  FIG. 1  being subjected to a pull-out force. 
     
    
    
     Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate exemplary embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention in any manner. 
     DETAILED DESCRIPTION 
     A pile driver  10  is shown in  FIG. 1  for driving a pile  100  into the soil S below the ground surface G. Pile  100  includes upper end  102 , lower end  104 , and longitudinal axis A that extends between upper end  102  and lower end  104 . The illustrative pile driver  10  is a vibratory pile driver including a vibratory housing  12  coupled to an articulating boom  14  of an excavator  16  and to upper end  102  of pile  100 . Pile driver  10  may also be configured to impact or otherwise drive pile  100  into the soil S. 
     Referring next to  FIG. 2A , the vibration of housing  12 , coupled with the weight of housing  12  atop pile  100 , causes pile  100  to travel downward into the soil S along longitudinal axis A. The articulating boom  14  may articulate relative to excavator  16  to guide housing  12  and pile  100  downward. When pile  100  vibrates in the soil S, particle-to-particle adhesion between the soil particles decreases, and the soil S becomes more flowable (i.e., quick-conditioned) to accommodate passage of pile  100 . Upper end  102  of pile  100  approaches the ground surface G, and lower end  104  of pile  100  sinks into the soil S below the ground surface G. When pile  100  stops vibrating in the soil S, particle-to-particle adhesion between the soil particles returns to hold pile  100  in place. 
     A first exemplary pile  100  is shown in more detail in  FIGS. 3 and 4 . The illustrative pile  100  is an H-pile having an H-shape when viewed in plan or cross-section, as shown in  FIG. 4 . Pile  100  includes a first exterior flange  110 , a second exterior flange  112  that is oriented substantially parallel to the first flange  110 , and an intermediate web  114  that extends between the first and second flanges  110 ,  112 , in a direction substantially orthogonal to the first and second flanges  110 ,  112 . 
     The material used to construct pile  100  may vary depending on the desired application of pile  100  (e.g., the load to be supported by pile  100 , the surrounding soil type). For example, pile  100  may be constructed of metal (e.g., aluminum), a metal alloy (e.g., hardened or mild steel), or another suitable material. 
     The dimensions of pile  100  may vary depending on the desired application of pile  100  (e.g., the load to be supported by pile  100 , the surrounding soil type). Pile  100  may have a width W P  (measured along first and second flanges  110 ,  112  in  FIG. 4 ) and a depth D P  (measured along intermediate web  114  in  FIG. 4 ) as small as about 4 in., 6 in., or 8 in., and as large as about 10 in., 12 in., 14 in., or more, or within any range defined between any pair of the foregoing values. Pile  100  may be substantially square-shaped, such that the pile width W P  is substantially equal to the pile depth D P . Also, first and second flanges  110 ,  112 , and intermediate web  114  of pile  100  may have a pile wall thickness T P  as small as about ⅛ in., ¼ in., or ⅜ in., and as large as about ½ in., ⅝ in., ¾ in., or more, or within any range defined between any pair of the foregoing values. As shown in  FIG. 1 , pile  100  may have an overall length L P  (measured along longitudinal axis A) as small as about 20 ft., 40 ft., or 60 ft., and as large as about 80 ft., 100 ft., or more, or within any range defined between any pair of the foregoing values. 
     According to an exemplary embodiment of the present disclosure, pile  100  is at least partially hollow. In general, the hollow interior space is defined between a first longitudinal wall located on a first side of a longitudinal plane (i.e., a plane that intersects and extends parallel to a longitudinal axis) and a second longitudinal wall located on a second side of the longitudinal plane. In the illustrated embodiment of  FIGS. 3 and 4 , for example, first flange  110  constitutes the first longitudinal wall located on a first side of longitudinal plane P (i.e., a plane that intersects and extends parallel to longitudinal axis A), and second flange  112  constitutes the second longitudinal wall located on a second side of longitudinal plane P. First and second flanges  110 ,  112 , are the outer-most or exterior-most longitudinal walls of the illustrative pile  100 . Also, as shown in  FIG. 4 , longitudinal plane P is a plane of symmetry through the illustrative pile  100 . 
     When the illustrative pile  100  is viewed along longitudinal axis A, as shown in  FIG. 4 , the first and second longitudinal walls, specifically the first and second flanges  110 ,  112 , are seen creating an envelope  122  around interior space  120 . In embodiments where first and second flanges  110 ,  112 , do not extend to or intersect longitudinal plane P, envelope  122  around interior space  120  may be formed by projecting the ends  111 ,  113 , of first and second flanges  110 ,  112 , respectively, onto longitudinal plane P, as shown in  FIG. 4 . By contrast, in embodiments where first and second flanges  110 ,  112 , bend or curve to intersect longitudinal plane P, envelope  122  around interior space  120  may be formed by first and second flanges  110 ,  112 , themselves. 
     In  FIG. 4 , intermediate web  114  is shown extending through interior space  120  between first and second flanges  110 ,  112 , of the illustrative pile  100 . More specifically, intermediate web  114  is shown bisecting interior space  120  of the illustrative pile  100 . Intermediate web  114  may occupy a minority (i.e., less than 50%) of the cross-sectional area of interior space  120 . For example, intermediate web  114  may occupy less than about 20%, 15%, 10%, or 5%, of the cross-sectional area of interior space  120 , or within any range defined between any pair of the foregoing values. 
     According to another exemplary embodiment of the present disclosure, pile  100  is open-ended to the hollow interior space, at least along its lower end. In the illustrated embodiment of  FIG. 2A , for example, pile  100  is open-ended to interior space  120  by virtue of lower end openings  124 A,  124 B, in lower end  104  that make interior space  120  open or accessible along lower end  104 . Lower end openings  124 A,  124 B, are located on opposite sides of intermediate web  114 . In use, soil S is able to enter interior space  120  of pile  100  through lower end openings  124 A,  124 B, in lower end  104 . The illustrative pile  100  also includes side openings  126 A,  126 B, into interior space  120 , so in addition to entering interior space  120  through lower end openings  124 A,  124 B, soil S may also enter interior space  120  through side openings  126 A,  126 B, as shown in  FIG. 2B . Side openings  126 A,  126 B, are located on opposite sides of intermediate web  114 . 
     Referring again to  FIGS. 3 and 4 , the illustrative pile  100  includes one or more anchors, illustratively two anchors  130 A,  130 B. Anchors  130 A,  130 B, of the illustrative pile  100  are located on opposite sides of intermediate web  114 . Anchors  130 A,  130 B, of the illustrative pile  100  are mirror images of one another. Each anchor  130 A,  130 B, includes a generally planar upper surface  132 , a generally planar lower surface  134 , an interior side  136  located adjacent to longitudinal axis A, and an exterior side  138 . In use, anchors  130 A,  130 B, may resist removal of pile  100  from the soil S, as discussed further below. 
     Anchors  130 A,  130 B, are located between upper end  102  and lower end  104  of the illustrative pile  100 , as shown in  FIG. 1 . Anchors  130 A,  130 B, may be spaced apart from upper end  102  of pile  100  by a longitudinal distance D A1  and from lower end  104  of pile  100  by a longitudinal distance D A2 . More specifically, anchors  130 A,  130 B, may be spaced apart further from upper end  102  than lower end  104 , such that distance D A1  to upper end  102  of pile  100  exceeds distance D A2  to lower end  104  of pile  100 . For example, distance D A1  to upper end  102  of pile  100  may be about 4 times, 6 times, 8 times, 10 times, or more greater than distance D A2  to lower end  104  of pile  100 . 
     Anchors  130 A,  130 B, occupy a longitudinal extent of the illustrative pile  100  having a length L A , as shown in  FIG. 1 . The length L A  occupied by anchors  130 A,  130 B, may comprise a small percentage of the overall length L P  of pile  100 . For example, length L A  occupied by anchors  130 A,  130 B, may comprise less than about 10%, 5%, 1%, or 0.5%, of the overall length L P  of pile  100 , or within any range defined between any pair of the foregoing values. 
     Anchors  130 A,  130 B, are located at least partially within interior space  120  of the illustrative pile  100 . In  FIGS. 3 and 4 , anchors  130 A,  130 B, are located entirely within interior space  120  of pile  100  without projecting beyond envelope  122 . In  FIGS. 5 and 6 , by contrast, the exterior sides  238  of anchors  230 A,  230 B, project outwardly from interior space  220  and beyond envelope  222  through side openings  226 A,  226 B, of pile  200 , respectively. As shown in  FIG. 5 , extension portion  239  of each anchor  230 A,  230 B, that projects outwardly from envelope  222  may have an extension width W E  (measured outwardly from envelope  222 ). The extension width W E  may be as small as about 0.25 in., 0.5 in., or 1 in., and as large as about 1.5 in., 2 in., 2.5 in., or more, or within any range defined between any pair of the foregoing values. 
     Anchors  130 A,  130 B, span across interior space  120  between flanges  110 ,  112 , of the illustrative pile  100 , as shown in  FIG. 4 . Anchors  130 A,  130 B, may be fixedly coupled to flanges  110 ,  112 , such as using spot welds  140 , adhesive, or mechanical fasteners, for example. When upper surfaces  132  of anchors  130 A,  130 B, or lower surfaces  134  of anchors  130 A,  130 B, are viewed along longitudinal axis A, as shown in  FIG. 4 , anchors  130 A,  130 B, may appear to occupy a majority (i.e., more than 50%) of the area of interior space  120 . For example, anchors  130 A,  130 B, may appear to occupy more than about 60%, 70%, or 80% of the area of interior space  120 , or within any range defined between any pair of the foregoing values. Stated differently, a projected area of anchors  130 A,  130 B, onto a perpendicular plane (i.e., a plane that is perpendicular to longitudinal axis A), as shown in  FIG. 4 , may comprise a majority of the area of interior space  120 . 
     Anchors  130 A,  130 B, of the illustrative pile  100  extend transversely (i.e., non-parallel) to longitudinal axis A, as shown in  FIG. 3 . Anchors  130 A,  130 B, may be angled downwardly in pile  100  from exterior sides  138  to interior sides  136 . In this arrangement, upper surfaces  132  of anchors  130 A,  130 B, define an acute angle α with longitudinal axis A, and lower surfaces  134  of anchors  130 A,  130 B, define an obtuse angle β with longitudinal axis A. The acute angle α may be as small as about 10 degrees, 20 degrees, 30 degrees, or 40 degrees, and as large as about 50 degrees, 60 degrees, 70 degrees, or 80 degrees, or within any range defined between any pair of the foregoing values. In  FIG. 3 , the acute angle α is about 30-40 degrees, and the corresponding obtuse angle β is about 140-150 degrees. The angles α and β may vary depending on the desired application of pile  100  (e.g., the load to be supported by pile  100 , the surrounding soil type). Together, the downwardly-angled anchors  130 A,  130 B, may form a V-shaped body in pile  100 . During insertion of pile  100  into the soil S, this V-shaped body may cut into the soil S. After insertion, this V-shaped body may resist removal of pile  100  from the soil S, as discussed further below. 
     Anchors  130 A,  130 B, of the illustrative pile  100  are spaced apart from each other and from intermediate web  114  to define at least one intermediate gap, illustratively two intermediate gaps  150 A,  150 B, between interior sides  136  of anchors  130 A,  130 B. Gaps  150 A,  150 B, are located on opposite sides of intermediate web  114 . In use, soil S in interior space  120  of pile  100  is able to travel from lower surface  134  to upper surface  132  of anchors  130 A,  130 B, through gaps  150 A,  150 B, respectively, as shown in  FIG. 2B . In the illustrated embodiment of  FIG. 3 , each gap  150 A,  150 B, between intermediate web  114  and interior side  136  of the corresponding anchor  130 A,  130 B, respectively, may have a gap width W G  as small as about 0.25 in., 0.5 in., or 1 in., and as large as about 1.5 in., 2 in., 2.5 in., or more, or within any range defined between any pair of the foregoing values. 
     After pile  100  is driven into the soil S, anchors  130 A,  130 B, may increase the pull-out resistance of pile  100  from the soil S. Pile  100  is shown being subjected to a pull-out force F in  FIG. 11 . Soil S may gather atop upper surfaces  132  of anchors  130 A,  130 B, and add weight to pile  100 , thereby resisting the pull-out force F. Additionally, anchors  130 A,  130 B, may transfer the pull-out force F outwardly into the soil S beyond pile  100 . In the illustrated embodiment of  FIG. 11 , for example, anchors  130 A,  130 B, transfer the pull-out force F to a pyramid-shaped zone Z of soil S located outwardly beyond pile  100 . Particle-to-particle adhesion between the soil particles in zone Z may further resist the pull-out force F. This particle-to-particle adhesion between the soil particles in zone Z may be more significant than the metal-to-particle adhesion between pile  100  and the surrounding soil S. 
     Another exemplary pile  300  is shown in  FIGS. 7 and 8 . The illustrative pile  300  is a circular tube pile having a circular longitudinal wall (i.e., a cylindrical wall). Although the longitudinal wall of pile  300  is illustratively a single, generally continuous, circular wall, pile  300  is described herein as having a first longitudinal wall  310  located on a first side of longitudinal plane P and a second longitudinal wall  312  located on a second side of longitudinal plane P, where the first and second longitudinal walls  310 ,  312 , are both semicircular in shape and are interconnected. These semicircular walls  310 ,  312 , cooperate to define a circular envelope  322  around interior space  320 . 
     A lower end opening  324  into interior space  320  may be provided to receive soil S in pile  300 , as shown in  FIG. 7 . However, because interior space  320  may be enclosed or surrounded by the first and second longitudinal walls  310 ,  312 , pile  300  may lack side openings into interior space  320  for receipt of additional soil S. 
     Other than anchors  330 A,  330 B, the illustrative pile  300  lacks other intermediate structures (e.g., an intermediate web) in interior space  320 . Without an intermediate web between anchors  330 A,  330 B, a single gap  350  may exist between anchors  330 A,  330 B, and this gap  350  may be aligned with longitudinal axis A. 
     If necessary, apertures  360  in the first and second longitudinal walls  310 ,  312 , may be provided, at least temporarily, to facilitate assembly of anchors  330 A,  330 B, in interior space  320  of pile  300 . For example, apertures  360  may facilitate receipt of spot welds  340 , adhesive, or mechanical fasteners, into interior space  320  of pile  300 . However, apertures  360  may be plugged or otherwise blocked after assembly. 
     Yet another exemplary pile  400  is shown in  FIGS. 9 and 10 . The illustrative pile  400  is a box tube pile having a rectangular longitudinal wall. Although the longitudinal wall of pile  400  is illustratively a generally continuous, rectangular wall, pile  400  is described herein as having a first longitudinal wall  410  located on a first side of longitudinal plane P and a second longitudinal wall  412  located on a second side of longitudinal plane P, where the first and second longitudinal walls  410 ,  412 , are both U-shaped and are interconnected. These U-shaped walls  410 ,  412 , cooperate to define a rectangular envelope  422  around interior space  420 . 
     While this invention has been described as having exemplary designs, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.