Abstract:
An apparatus and method for engaging a member within a soil formation. The apparatus comprises a shaft extending between top and bottom ends along a central axis and having at least one auger section therearound and a first plate, axially rotatably connected to the shaft. The apparatus may further comprise a second plate rotatably connected to the shaft above the first plate which may have connectors for engagement with a corresponding adjacent plate. The method comprises locating the shaft above a soil formation and rotating the shaft into the soil formation so as to draw the first plate into the soil formation.

Description:
BACKGROUND OF THE DISCLOSURE 
       [0001]    1. Field of Disclosure 
         [0002]    The present disclosure relates to construction in general and in particular to a method and apparatus for engaging a member within a soil formation. 
         [0003]    2. Description of Related Art 
         [0004]    At many worksites, it is frequently necessary to engage a construction member within the ground for the purposes of securing the member therein or to reinforce or retain a portion of the ground behind the member. Such members may commonly be located within the soil formation by pile driving wherein the member is forcibly pressed into the ground by a backhoe, pile driver or the like. One example of when such methods may be utilized is for locating pilings within the ground. 
         [0005]    One disadvantage of such methods is that the force required to drive such a member into the ground can be high requiring relatively large equipment or relatively small members to effectively penetrate the ground. It will be appreciated that such limitations often limit the size of ground penetrating members that may be used in some locations where larger equipment is not able to access. 
         [0006]    Another common method of locating the member within the soil formation is to excavate the location where the member is to be located and thereafter backfilling against the member. In particular, one situation in which such methods are used is where it is necessary to excavate a hole to access a buried structure or to expose a location where the work is to occur. In many instances, it is not practical to excavate a large amount of soil due to the proximity of other structures or time constraints. In such circumstances, it is common to excavate a relatively narrow hole or trench and provide reinforcement or shoring to the trench or hole walls to prevent their collapse. 
         [0007]    Conventional shoring methods have been to provide timbers or metal plates braced against opposing sides of the trench or hole or braced to a bottom of the hole or trench. Such conventional shoring has several disadvantages. In particular, shoring using a plurality of timbers may be time consuming and inaccurate to install as each timber must be located individually. Furthermore, after the timers are located, they must be secured to each other and thereafter braced against an opposite wall. These multiple steps increase the amount of time required to shore the excavation. 
         [0008]    Other methods have been to provide a shoring structure comprising a pair of spaced apart steel plates having a plurality of struts therebetween. Disadvantageously, such shoring structures are also required to either be assembled within the excavation or pre-assembled and lowered into the excavation as a whole. Where the assembled structure is lowered into the excavation as a whole, it may be possible for the shoring structure to partially collapse or otherwise impact and thereby disturb the excavation wall. 
         [0009]    An additional difficulty with current excavation shoring methods, is that it is necessary to excavate the location before the shoring is put into place. In many soil types, such as, for example, moist or soft soils, such unshored excavations may be prone to wall collapse before the shoring can be properly located. The struts and other bracing members between shoring walls may also limit the access that workers and equipment has to the bottom of the shored excavation. 
         [0010]    SUMMARY OF THE DISCLOSURE 
         [0011]    According to a first embodiment of the present disclosure there is disclosed an apparatus for engaging a soil formation comprising a shaft extending between top and bottom ends along a central axis and having at least one auger section therearound and a first plate, axially rotatably connected to the shaft. 
         [0012]    The at least one auger section may be proximate to the bottom end of the shaft. The shaft may include a second auger section located below the first plate. 
         [0013]    The first plate may be located proximate to the top end of the shaft. The first plate may be located at substantially a midpoint of the shaft. The first plate may be longitudinally located along the shaft. The first plate may be longitudinally located along the shaft by collars. The first plate may extend substantially radially from the shaft. The first plate may include a top edge extending substantially perpendicularly from an axis of the shaft. The plate may include a bottom edge extending at an angle of incline from a plane normal to the axis of the shaft. 
         [0014]    The apparatus may further comprise a second plate rotatably connected to the shaft above the first plate. The second plate may be substantially alignable with the first plate. The second plate may be independently rotatable of the first plate. The second plate may extend between first and second side edges. The first and second side edges may be substantially parallel with the central axis. The first and second side edges may have connectors for engagement with a corresponding adjacent plate. The connectors may comprise a u-shaped channel adapted to intermesh with corresponding u-shaped channel of adjacent plates so as to be interlocked therewith. 
         [0015]    Each u-shaped channel may comprise a flange extending from each of the first and second side edges to a parallel spaced apart end plate. 
         [0016]    According to a further embodiment of the present disclosure there is disclosed a method for engaging a member within a soil formation comprising locating a shaft extending between top and bottom ends along a central axis and having at least one auger section therearound and having a first plate, axially rotatably connected to the shaft above a soil formation and rotating the shaft into the soil formation so as to draw the first plate into the soil formation. 
         [0017]    The method may further comprise interlocking a second plate rotatably connected to the shaft to an adjacent plate. 
         [0018]    Other aspects and features will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments in conjunction with the accompanying figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    In drawings which illustrate embodiments wherein similar characters of reference denote corresponding parts in each view, 
           [0020]      FIG. 1  is an illustration of an excavation site having an apparatus for shoring the excavation located thereabove. 
           [0021]      FIG. 2  is a perspective view an apparatus for shoring an excavation site according to a first embodiment of the present invention. 
           [0022]      FIG. 3  is a cross sectional view of the apparatus of  FIG. 2  as taken along the line  3 - 3 . 
           [0023]      FIG. 4  is a side view of the apparatus of  FIG. 2  being inserted into the soil formation. 
           [0024]      FIG. 5  is a perspective view of the apparatus of  FIG. 2  having an optional soil retaining extension. 
           [0025]      FIG. 6  is a cross sectional view of two soil retaining extensions of  FIG. 5  as taken along the line  5 - 5  interlocked with each other to form a barrier. 
           [0026]      FIG. 7  is a side view of a piling apparatus according to a further embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    With reference to  FIG. 1 , an apparatus for engagement within a soil formation  10  according to a first embodiment of the present invention is generally illustrated at  20 . The apparatus comprises an elongate shaft  22  having at least one auger  40  extending therearound and a plate  50  rotatably supported at a fixed location therealong. The apparatus  20  is operable to be rotated by a piece of equipment  8 , such as, by way of non-limiting example, an excavator, skid steer loader or crane such that the augers  40  and  42  draw the apparatus into the soil formation  10  as will be more fully described below. 
         [0028]    The shaft  22  extends between bottom and top ends,  24  and  26 , respectively and may have a length of between 12 to 20 feet (3658 and 6096 mm) although it will be appreciated that other lengths may be useful as well. As illustrated, the bottom end  24  of the shaft may be sharpened to ease insertion into a soil formation and the top end may have a plurality of transverse bores  28  therethrough or other suitable means for being gripped by an excavator  8 . The shaft  22  includes first and second collars,  30  and  32 , respectively. The first and second collars  30  and  32  are spaced apart by a distance sufficient to retain the plate  50  therebetween, such as, by way of non-limiting example between 1 to 16 feet (305 and 3658 mm). The collars  30  and  32  may be secured to the shaft by any suitable means, such as, by way of non-limiting example, fasteners, welding or being formed integrally therewith. The shaft  22  and collars  30  and  32  may be formed of any suitable material, such as, by way of non-limiting example steel, stainless steel or other metals and alloys. 
         [0029]    A first auger  40  surrounds the shaft  22  proximate to the bottom end  24  thereof. As illustrated, the apparatus  20  may also include a second auger  42  located thereabove at a position below the plate  50 . It will also be appreciated that the first and second augers  40  and  40  may be interconnected with each other to form a continuous auger section extending between the bottom end  24  of the shaft to a location below and proximate to the plate  50 . The plate  44  extends substantially radially from the shaft by a distance selected to ensure the auger will draw the apparatus into the soil formation under rotation, such as between 6 and 18 inches (152 and 457 mm) depending upon the soil type for which the apparatus is intended to be used. With reference to the first auger  40 , each auger may be formed of a plate  44  of material spirally surrounding the shaft between top and bottom ends,  46  and  48 , respectively. The bottom end  48  may optionally be sharpened or tapered to facilitate insertion into the soil formation. Each auger may have a pitch angle selected to draw the apparatus  20  into a soil formation when the shaft is rotated. Each auger  40  or  42  may surround the shaft  22  in as many rotations as is desired by a user, such as, by way of non-limiting example ½ rotation or more. The augers may be formed of any suitable material, such as, by way of non-limiting example steel or stainless steel and may be secured to the shaft in any suitable manner, such as, by way of non-limiting example, welding fasteners or the like. 
         [0030]    The plate  50  comprises a central sleeve  52  having a pair of substantially planar members  54  extending radially therefrom. The central sleeve  52  extends between top and bottom ends,  56  and  58 , respectively and includes a central bore  60 , as illustrated in  FIG. 3  sized to rotatably surround the shaft  22 . The collars  30  and  32  abut against the top and bottom ends  56  and  58  of the sleeve to retain the sleeve therebetween. Each planar member  54  extends between top and bottom edges,  62 , and  64 , respectively. The top edges  62  may be substantially perpendicular to the shaft, although other orientations and profile shapes may be useful as well. The bottom edge  64  may be inclined from a plane normal to the shaft by an incline angle, generally indicated at  66 . The incline angle  66  facilitates insertion of the plate  50  into the soil formation as the shaft  22  is rotated and may be selected from any angle between 30 and 60 degrees. Optionally, the bottom edge  64  of the planar members  54  may be sharpened or tapered to assist with insertion into the soil formation. The plate may have a height between the top and bottom edges selected to provide a sufficient excavation depth, such as, by way of non-limiting example, between 1 and 6 feet (305 and 1829 mm). 
         [0031]    With reference to  FIG. 1 , in operation, a piece of equipment, such as, by way of non-limiting example, an excavator, skid steer loader or the like, may engage the transverse bores  28  of the apparatus with a rotary auger drive as are commonly known. Thereafter, the apparatus  20  may be located above a soil formation  10  and rotated in a direction generally indicated at  70  so as to engage the augers  40  and  42  into the soil formation. While being rotated, the augers  40  and  42  draws the apparatus into the soil formation until the plate  50  is embedded within the soil formation. Once the plate  50  is embedded to a sufficient depth into the soil formation, the apparatus may be decoupled from the piece of equipment and the soil proximate to the plate may be excavated such that the plate shores excavation site. 
         [0032]    Optionally, the apparatus may include a soil retaining extension  80  as illustrated in  FIG. 5 . The soil retaining extension  80  may comprise a plate  81  extending between top and bottom ends,  82  and  84 , respectively and first and second side edges,  86  and  88 , respectively. The plate  81  includes a central bore section  90  having a plurality of sleeves  92  therein having bores  94  therethrough sized to receive the shaft  22  of the apparatus. The bores  94  of the sleeves  92  pivotally retain the soil retaining extension  80  on the shaft  22 . With reference to  FIG. 6 , each of the first and second sides edges includes a return edge lip  87  and  89 , respectively. The return edges lips  87  and  89  may be arranged to opposite or the same sides of the plate  81  and are adapted to be interlocked with adjacent return lips of adjacent apparatuses as illustrated in  FIG. 6  so as to permit the formation of a continuous barrier. As illustrated in  FIG. 5 , the soil retaining extension  80  may be retained on the shaft  22  with a collar  96  as will be commonly known. In such embodiments, in operation, the apparatus  20  may be rotated into a soil formation as set out above with the plate  50  below an in planar alignment with the soil retaining extension  80 . Thereafter the soil proximate to the soil retaining extension  80  may be excavated with the plate  50  remaining below the depth of the excavation so as to provide additional stability to the shaft  22  and the soil retaining extension. 
         [0033]    Turning now to  FIG. 7 , an alternative embodiment of the present invention is illustrated generally at  100  for use as a screw piling. The screw piling  100  comprises a shaft  102  extending between bottom and top ends,  104  and  106 , respectively with a plate  120  rotatably supported therearound. The shaft  102  may have a length of between 6 to 12 feet (1829 and 3658mm) although it will be appreciated that other lengths may be useful as well. As illustrated, the bottom end  104  of the shaft may be sharpened to ease insertion into a soil formation and the top end may have a plurality of mounting bores  107  for connection to beams, columns or the like as are commonly known. The shaft  102  may also include top and bottom augers  110  and  108  as described above. The shaft  102  includes top and bottom collars,  112  and  114 , respectively and an optional middle collar  116 . The top and bottom collars  112  and  114  are spaced apart by a distance sufficient to retain the plate  120  therebetween, such as, by way of non-limiting example between 8 to 16 feet (2438 and 3658 mm). The collars  112 ,  114  and  116  may be secured to the shaft by any suitable means, such as, by way of non-limiting example, fasteners, welding or being formed integrally therewith. The shaft  102  and collars  112 ,  114  and  116  may be formed of any suitable material, such as, by way of non-limiting example steel, stainless steel or other metals and alloys. 
         [0034]    The plate  120  comprises a central sleeve  122  having a pair of substantially planar members  124  extending radially therefrom. The central sleeve  122  extends between top and bottom ends,  128  and  126 , respectively and surrounds the shaft  102 . The top and bottom collars  112  and  114  abut against the top and bottom ends  128  and  126  of the sleeve to retain the sleeve therebetween. Each planar member  124  extends between top and bottom ends,  128 , and  126 , respectively. The top end  128  may be substantially perpendicular to the shaft, although other orientations and profile shapes may be useful as well. The bottom edge  126  may be inclined from a plane normal to the shaft by an incline angle as set out above. The planar members  124  and sleeve  122  may include a central opening  130  which is located around the middle collar  116 . The planar members  124  extend radially from the plate by a distance sufficient to increase ability of the shaft to resist lateral loads placed thereupon such as, by way of non-limiting example, between 4 and 12 inches (102 and 305 mm). The top end  106  of the shaft  102  may extend above the top end  128  of the plate  120  by a distance sufficient to permit the plate to be embedded below the surface of the soil when the top end  106  of the shaft is proximate to the ground surface. By way of non-limiting example, the top end  106  of the shaft may be up to 6 feet (1829 mm) above the top end  128  of the plate. 
         [0035]    While specific embodiments of the invention have been described and illustrated, such embodiments should be considered illustrative of the invention only and not as limiting the invention as construed in accordance with the accompanying claims.