Abstract:
A concrete forming panel and its method of use is provided wherein the forming panel has a face plate including a frame, a front side and a back side, and one or a plurality of pairs of ribs which extend longitudinally along the back side. The pairs of ribs are provided sufficiently closely together to grip an element passing through the face plate or to grip a wedge which in turn engages the element. The element may be a nail, stake, or other fastener used to hold the forming panel in the ground, to connect the forming panel to other forming panels, or to indicate a desired level for concrete poured against the front side to be cured and hardened into a finished structure, such as a foundation for a building. The ribs may be provided with slots for receiving a reinforcing element of a relatively harder material, and the reinforcing element may be shiftably received in the slot so that its position may be changed as the reinforcing element wears during use.

Description:
RELATED APPLICATION  
       [0001]    This application relates to and claims the benefit of priority of prior copending U.S. Provisional Application No. 60/420,807, filed Oct. 23, 2002, said Provisional Application being hereby incorporated by reference into the present specification. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    This invention relates to a concrete forming panel which includes a forming face which has a reinforcement on the rear side of the forming face adapted for gripping elements removably attached thereto. The reinforcement is configured to resist expansion of openings through the forming face. More particularly, it is concerned with a concrete form and method of its use in connection with the pouring of low concrete walls or pads where the form may be held in place by stakes driven into the ground.  
           [0004]    2. Description of the Prior Art  
           [0005]    The formation of concrete walls and pads is well known and often involves the use of wooden or metal forms. Metal forms are more expensive, but also more durable and may be repeatedly used. When concrete pads are to be poured in residential construction, there is a need for concrete forms which can be quickly and economically set up and dismantled for use at the next site. Examples of known forming panels include those shown in U.S. Pat. Nos. 4,708,315, 4,958,800, 5,058,855, 5,184,439 and 5,965,053, the disclosures of which are incorporated by reference herein.  
           [0006]    One problem especially presented by the use of metal forms for pouring foundations such as concrete pads involves their use on rough ground. The metal forms have a permanent shape, and there is a desire to avoid permanently altering or damaging the forms by drilling openings to receive tie rods, bars or tensioning cables therethrough, or driving nails through the frame or face plate of the form to indicate level lines so that the concrete can be poured to a desired depth with a level, horizontal surface. Also, rocks, stumps or other solid objects maybe buried just below grade, and stakes conventionally used for anchoring the forms may encounter such objects. are particularly presented in using concrete forms for form.  
           [0007]    In addition, it is known to post-tension concrete slabs by the use of such tensioning cables. Post-tensioning concrete slabs uses tensioning cables surrounded by sheaths which are positioned in the pouring area and after the poured concrete is hardened, stretching the cable by applying tensioning at the ends through the use of a stressing jack and then anchoring the cable ends in the concrete. Such a practice improves the response of the resulting concrete slab to loading, and reduces deflections and cracking. Further, the use of post-tensioning in concrete slabs may result in slabs which are generally thinner, relatively longer, and reducing the weight of the resulting poured structure. However, in order to initially position the live end anchor which is typically received within a cone to create a pocket for access after concrete hardening and the dead end anchor which is encased within the hardened concrete, it has been heretofore largely necessary as a practical matter to employ wooden forms which must be discarded after use.  
           [0008]    There is thus a need for an improved concrete forming panel and method of use which overcomes these problems.  
         SUMMARY OF THE INVENTION  
         [0009]    These and other needs are largely met by the concrete forming panel of the present invention. That is to say, the concrete forming panel hereof is particularly useful in forming foundations such as concrete pads where it is desirable to anchor the forming panel to the ground by stakes, and wherein the forming panel may need to be penetrated through the front side of the face plate. To this end, the concrete forming panel hereof includes at least one and preferably a plurality of sets of reinforcing ribs on the back side of the face plate which are configured and position for gripping a variety of elements passing through the face plate, either themselves or with the use of wedges depending on the orientation of the element relative to the front side of the face plate.  
           [0010]    Broadly speaking, the concrete forming panel of the present invention includes a face plate having a frame, a front side and a rear side, and at least one set of reinforcing ribs received on the back side, the ribs being positioned closely adjacent one another and parallel for gripping objects placed therebetween. The face plate may be formed with a face panel having the front side and rear side which is separate from the frame, or a portion of the frame may be cast by extruding or the like or forged so that the face panel is integral with some of the rails and the reinforcing ribs. The elongated reinforcing ribs preferably extend longitudinally along the back side of the face plate, but alternatively or in addition may extend along the frame. The face plate and the ribs are preferably provided of aluminum, which as used herein includes both elemental aluminum and alloys wherein the primary constituent is aluminum. Because aluminum is relatively soft and subject to wear, the ribs may include longitudinally extending slots which receive therein reinforcing elements of a harder material, such as steel. Most preferably, the reinforcing elements are shiftably received in the slots, thereby permitting the reinforcing elements to be moved along the slots to vary the locations where wear occurs and also permitting the reinforcing elements to be located to engage an element to be gripped.  
           [0011]    The face plate is preferably provided with opposing top and bottom rails, and at least one set of holes in the frame on each of the top and bottom rails. A stake may be placed through one of the holes of each set, so that the stake penetrates the ground and holds the forming panel in place. The stake may be positioned perpendicular or skew to the rails to avoid rocks or other impediments to penetration into the soil. The ribs may themselves engage the stake, or more preferably a wedge may be placed between the ribs and engage the stake to secure it and therefore the form in the desired placement. The wedge may be driven into engagement with the stake by a hammer or the like, whereby the face plate is firmly held in place. Two or more stakes may be used to resist movement of the forming panel.  
           [0012]    It may also be desirable to provide openings in through the face side of the face plate for the passage of tie rods, anchoring cables or the like. After their use, the openings would permit leakage of concrete therethrough. However, the forming panel of the present invention permits these holes to be plugged through the use of elements such as plugs or the like which may be gripped by the ribs. This not only permits the forming panel to be reused, but permits removal of the elements as desired when it is again necessary to use the opening.  
           [0013]    Further, it may be desirable to penetrate the face plate during its use. Because the face plate is preferably provided of aluminum, a nail or other fastener may be driven through the face plate so that it passes between the ribs. The nail may be used to connect the forming panel to lumber on a face of the forming panel or to wood forming panels, reinforcements or stakes. This may be especially advantageous where tensioning cables are used to hold spaced-apart and opposed panels in position during the pouring and curing of the concrete, and there is a need to attach the cable to the panel.  
           [0014]    These and other advantages will be readily apparent to those skilled in the art with reference to the drawings and the description of the preferred embodiment which follows. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is a rear perspective view of a concrete forming panel in accordance with the present invention, showing the reinforcing ribs along the back side of the face plate, the concrete forming panel being anchored to the ground by stakes and connected to and opposing other forming panels by live end and dead end anchors and tensioning cables passing through a pouring area between the forming panels for receiving flowable concrete for curing and hardening;  
         [0016]    [0016]FIG. 2 is a rear elevational view thereof, showing one of the stakes perpendicular to the upper rail and another stake skew thereto, and showing in dashed lines the position of a stake when held by a hanger on the forming panel;  
         [0017]    [0017]FIG. 3 is an enlarged, fragmentary horizontal cross-sectional view taken along line  3 - 3  of FIG. 2, showing the receipt of a plug element in an opening extending through the face panel of the face plate, a reinforcing rod received in a slot in the reinforcing ribs, and a wedge gripped between the ribs;  
         [0018]    [0018]FIG. 4 is an enlarged, fragmentary vertical cross-sectional view taken along line  4 - 4  of FIG. 3, showing a nail fastener penetrating through the front side of the face plate and gripped between one of the pairs of reinforcing ribs for attachment of wood blocks or the like to the panel; and  
         [0019]    [0019]FIG. 5 is an enlarged, fragmentary vertical cross-sectional view taken along line  5 - 5  of FIG. 2, showing the plug element gripped by a pair of ribs and a hanger for retaining the stake prior to use, the hanger including an elastomeric grommet. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0020]    Referring now to the drawings, a forming panel  10  for use in forming structures from flowable cementatious material such as concrete broadly includes a face plate  12  and at least one, and preferably a plurality of pairs of, reinforcing ribs  14 . A hanger  16  may be provided for holding a steel stake  18  used with the forming panel  10 . A fastening element  20  may be used with the forming panel  10 , and one or a plurality of plug elements  22  may be used to close openings in the face plate  12 . As shown in FIG. 2, the forming panel  10  is particularly useful for forming foundations such as concrete pads which rest directly on the ground  24 .  
         [0021]    In greater detail, the face plate  12  is preferably fabricated of an aluminum alloy such as ASTM 6061 T-6, and includes a frame  26  and a face panel  28  having a front side  30  and a back side  32 . The frame  26  preferably includes a top rail  34  and a bottom rail  36 , and first and second side rails  38  and  40  which together with the back side  32  of the face panel  28  define a rear area  41  inwardly of the margins of the rails. The face panel  28  may be formed separately and welded to the frame  26 , or alternatively as shown in the drawings, the face panel  28  and top and bottom rails may be integrally formed by casting, such as extrusion, and the side rails  38  and  40  then welded to the extrusion. The frame  26  including the rails is fabricated of a greater thickness of material along at least some parts thereof than the face panel  28 .  
         [0022]    The top rail  34  and the bottom rail each include at least one, and preferably a plurality of sets  42  of holes  44  therethrough. As used herein, a set  42  of holes  44  is meant to mean a plurality of holes  44  more closely spaced together than the distance between holes  44  of different sets  42 . As shown in FIG. 1, the top rail  34  thus includes four sets  42 A,  42 B,  42 C and  42 D of three holes  44  each, and the bottom rail  36  includes four sets  42 E,  42 F,  42 G and  42 H of three holes  44  each, the set  42 A being positioned in registry above and opposite the set  42 E, and the same respective relationship existing between set  42 B and  42 F, set  42 C and  42 D, and set  42 D and  42 G.  
         [0023]    In addition, the side rails  38  and  40  are each provided with a plurality of holes  44  for receiving therethrough couplers, such as pins  46  and their associated wedges for coupling the forming panel  10  to similar or compatible adjacent forming panels as shown in FIGS. 1 and 2. Furthermore, the side rails  38  and  40  may include recesses  48  on their outer surface which, in some applications, may facilitate the receipt of tie bars or the like which may be secured by pins  46  for connecting the forming panel  10  to an opposite forming panel  10 A or to an adjacent forming panel. A pouring area  50  into which flowable concrete maybe poured is located between opposed forming panels  10  and  10 A for forming the structure between front sides of the opposing face panels. The face panel  28  may be smooth or textured on its front side  30 , texturing being provided to form a pattern to be imparted to the concrete hardening thereagainst, such as a brick pattern.  
         [0024]    The pairs of reinforcing ribs  14  preferably extend longitudinally across the back side  32  and may either extend the width of the form between the side rails  38  and  40  as shown with respect to the pair of reinforcing ribs  14 C, or may be interrupted by openings  52  in the face panel  28  as shown by pairs of reinforcing ribs  14 A and  14 B as described below. Each pair of ribs  14  includes an elongated first rib  54  and an elongated second rib  56  which are preferably mirror images and cantilevered from the back side  32  of the face panel  28 . The ribs  54  and  56  may be cast by extrusion or the like as a part of the face plate  12  as shown in FIGS. 4 and 5, or may formed separately and secured by welding, brazing or the like to the face panel  28 .  
         [0025]    Each of the ribs  54  and  56  preferably includes a longitudinally extending slot  58  which faces the opposite rib and the gap  60  therebetween, so that the slot  58  communicates with the gap  60 . The gap  60  is preferably less than about  25  centimeters across between the ribs in order that the ribs  54  and  56  of each pair  14  may grip elements received therebetween. One or a plurality of reinforcing elements  62  are preferably of a shorter length than the ribs and thus slidably received in the slot  58  which permits the reinforcing elements  62  to be shifted longitudinally along the slot.  
         [0026]    The reinforcing elements  62  are preferably steel rods  64 . Aluminum has a much lower hardness than steel (about 30 on the Brinnell hardness scale (Bhn) for cold rolled ASTM 6061 aluminum versus a Bhn number of about 111 for hot rolled SAE 1020 steel and a Bhn of 179 for hardened, tempered SAE 1020 steel). Thus, the use of the steel reinforcing element  62  greatly reduces wear on the ribs. The use of steel for the reinforcing element  62  also provides increased strength to the rib  54  or  56  to which it is attached. For example, ASTM 6061 aluminum has a tensile strength of about 20,000 to 40,000 psi and a yield strength of about 8,000 psi, whereas hot rolled SAE 1020 steel has a tensile strength of about 55,000 psi and a yield strength of about 30,000 psi and hardened, tempered SAE 1020 steel has a tensile strength of about 90,000 psi and a yield strength of about 60,000 psi. A particularly preferred steel for use as the wear element is an ASTM-228-93 steel wire having a tensile strength of about 254,000 psi to about 259,000 psi and a Bhn of about 518 to 529.  
         [0027]    The hanger  16  is provided for retaining the stake  18  in place on the form when form  10  is not in use. The hanger  16  is typically provided of two aluminum brackets  64  and  66  longitudinally spaced along the back side  32  and secured thereto by welding, brazing, rivets or the like, each having a passage  68  of sufficient size to receive the stake  18  therethrough as shown in FIGS. 1 and 2. At least one of the brackets  64 ,  66  includes an elastomeric grommet  70  of synthetic resin or rubber to grip and hold the stake.  
         [0028]    As shown in FIGS. 3, 4 and  5 , the pairs of reinforcing ribs  14  are configured to grip elements received in the rear area  41 . Openings  52  may be provided in the forming panel  10 , preferably along the longitudinal length of the pairs of reinforcing ribs  14 , to permit the use of tie rods or cables which must pass through the face plate  12 . When it is desired to block or close an opening  52  in the face plate  12  which extends from the front side  30  through to the rear side  32 , a plug element  22  may be held by the opposing ribs  54  and  56 . The plug  22  preferably is provided of aluminum or other durable material, but may also be provided of synthetic resin or rubber and includes a central, substantially cylindrical body  72  and wings  74  extending diametrically opposite therefrom. The body  72  may be placed in the opening  52  with the ribs  54  and  56  holding the wings  74  as shown in FIGS. 1, 2,  3  and  5 .  
         [0029]    The pairs of reinforcing ribs  14  are also useful to grip a fastening element  20 , such as a nail  76  driven through the face plate  12 . The nail  76  penetrates the face plate  12  which is typically of aluminum, and then may be gripped between the rods  64  as shown in FIG. 4 to provide steel-to-steel contact and thus avoid wear to the face plate  12 , the cantilevered arrangement of the ribs  54  and  56  permitting them to yield and thus grip the nail. Nails  76  or other fastening elements  20  are useful if a piece of wood  77  needs to be attached to the forming panel  10 , or when an anchor  78  is used when a tensioning cable  79  received in a surrounding sleeve (not shown) is passed through the pouring area and connected to the anchors  78  for anchoring an end of the cable  79 . The head of the nail  76  may be exposed to facilitate removal of a piece of wood or the anchor. The provision of several pairs of reinforcing ribs  14 A,  14 B and  14 C is especially useful for receiving and gripping nails  76  at different heights for different depths of concrete.  
         [0030]    In addition, the pairs of reinforcing ribs  14  are particularly useful in connection with fixing the reinforcing panel  10  relative to the stakes  18 . The position of the holes  44  in each set  42  causes the stakes to pass through the rear area  41 . Retaining elements such as wedges  80  of mild steel or other suitably hard material may be provided for receipt in the gap and gripping by the ribs  54  and  56 . The wedges  80  are shown in detail in FIG. 3 and are preferably flat and of a thickness complemental to the gap  60 .  
         [0031]    The wedges have a front margin  82  and a back margin  84  which is at an acute angle relative to the front margin. Fingers  86  and  88  are located along the sides of the wedge  80  and extend toward the back margin  84  to aid in placement of the wedge in the gap and permit driving of the wedge  80  longitudinally along the pair of reinforcing ribs  14  which receives it. The depth between the front margin  82  and back margin  84  thus varies as shown in FIG. 3, whereby a stake received in the holes  42  may initially pass by the narrowest part of the wedge  80 , and the wedge then driven longitudinally along the pair of reinforcing ribs  14  receiving it until the back margin  84  engages the stake  18  as shown in FIG. 3. Because the holes  42  have a greater diameter than the diameter of the stakes  18 , the stake may be angled to avoid rocks  90  in the ground as shown in FIG. 2, but the forming panel  10  may nonetheless remain fixed to the stake  18  whether the stake is substantially perpendicular to the top rail or at an acute angle thereto, each of which is shown in FIG. 2.  
         [0032]    [0032]FIGS. 6, 7 and  8  illustrate an alternative forming panel  10 B in accordance with the present invention, with like numbers used to indicate features common to forming panels  10  and  10 A, wherein the face plate  12 B includes a frame  26 B having first and second side rails  38 B and  40 B, top rail  34 B and a bottom rail (not shown), and wherein the pairs of reinforcing ribs  14 B are integrally formed with hats  94 . The hats  94  may extend either parallel to the top and bottom rails  34 B and  36 B or extend perpendicular or at other angles relative to the top and bottom rails as shown in FIG. 6.  
         [0033]    The frame  26 B may also include reinforcing plates  96  of steel or aluminum alloy which are interior to the rails and serve to reinforce the rails in the vicinity of the holes  44  through the rails. The hats  94  serve to reinforce the face panel  28 B against deflecting loads imparted by the cementations material received thereagainst, and preferably include sloping sidewalls  98  and  100  connected by stretch  102 . The pairs of reinforcing ribs  14 B are preferably integrally formed by extrusion as a part of the hat  94 , and as shown in FIGS. 7 and 8, are positioned adjacent each of the sloping sidewalls  98  and  100 .  
         [0034]    The ribs  54 B and  56 B are similar in configuration to ribs  54  and  56 , but include a web  104  connecting the ribs  54 B and  56 B. The web  104  lies against the back side  34 B of the face panel  28 B. The web  104  may be provided with elongated slots  106  at longitudinally spaced intervals therealong to facilitate the passage of fastening elements  20  through the web and the face panel, so that openings  108  created by drilling or driving a nail through the face panel are in registry with the slots  106 . Reinforcing elements  62 B such as rods  64 B are received in slots  58 B in each of the ribs  54 B and  56 B so that the rods  64 B oppose one another to grip elements inserted therebetween as described with regard to the forming panel  10 .  
         [0035]    In use, the forming panels  10 ,  10 A or  10 B hereof are assembled into forming walls  92  by the use of couplers, and depending on the distance between opposing forming walls, tie bars, tie rods, cables or other connecting structures may be used to hold the forming walls in the desired shape. When cables or tie rods are used which must pass through the forming panel  10 , they pass through the openings  52  in the face plate  12 . Otherwise, plugs  22  are used to close the openings, the plugs being held in place by the clamping action of the ribs  54  and  56  of a pair  14 .  
         [0036]    The wedges  80  are placed at desired locations along the length of the pairs of reinforcing ribs  14  proximate to the desired alignment for the corresponding holes  42  of a particular set  40  where the stake  18  is to pass through. The stake  18  is removed from the hanger  16  and driven into the ground, and then the wedge  18  is driven longitudinally along one of the pairs of reinforcing ribs  14  until it engages with the stake  18 . If desired, nails may be driven through the face plate  12  to attach pieces of wood for use as a part of the forming wall or as otherwise needed. Concrete is then poured into the pouring area  50  between the forming walls and against the front side  30 . After curing and hardening of the concrete into the pad or other concrete structure, the stakes are pulled and the forming walls  92  are disassembled for reuse.  
         [0037]    As shown in FIG. 1, the forming panel  10  is useful in connection with a post tensioning system, where anchors  78  include both dead end anchor  110  and live end anchor  112 , and a cone  114  is provided between the live end anchor  112  and the forming panel to create a pocket for access. The cable  79 , having a first end  116  connected and fixed to the dead end anchor  110  and a second end  118  which initially passes through the live end anchor  112 , extends through the pouring area between the forming panels  10  and through an opening  52  in the face plate. The anchors  78  maybe held in place by nails driven into the form and gripped by the ribs  14  prior to pouring of the concrete. After the concrete is hardened, the forming panels  10  may be removed, the dead end anchor  110  holding the first end of the cable being encased in the concrete. The cable, permited to shift because it is encased within its sheath, then has its second end  118  connected to a stressing jack to apply a tensioning load on the cable  79 . This tensioning force is transmitted to both of the anchors when the tensioned cable is fixed to the live end anchor  112 . As a result, the tension is then imparted to hardened concrete because the anchors  78  are embedded in the hardened concrete. The cone  114  creating a pocket in the concrete may then be filled and grouted.  
         [0038]    Although preferred forms of the invention have been described above, it is to be recognized that such disclosure is by way of illustration only, and should not be utilized in a limiting sense in interpreting the scope of the present invention. Obvious modifications to the exemplary embodiments, as hereinabove set forth, could be readily made by those skilled in the art without departing from the spirit of the present invention.  
         [0039]    The inventors hereby state their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of their invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims.