Patent Document

RELATED APPLICATIONS 
     This application claims priority from earlier filed U.S. Provisional Application Ser. No. 60/183,399, filed Feb. 18, 2000. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to systems for forming concrete structures. More specifically, the present invention relates to an all steel overhang system for use when forming an overhanging portion of a concrete structure, such as a portion of a bridge deck or a floor, and that protrudes in cantilever fashion from a supporting structure. 
     BACKGROUND OF THE INVENTION 
     In concrete construction modular forming systems for forming concrete walls are generally well known in the art. Modular forming systems for concrete walls are generally favored by contractors because such modular systems permit the rapid assembly, disassembly, and reuse of the forms, thus offering significant savings in terms of time, labor, and materials. Moreover, the use of a discrete number of pre-manufactured wall form sections permits the construction of wall having different height, length, and thickness simply by choosing modular sections of the desired size. 
     When constructing bridges having concrete bridge decks, frequently a portion of the bridge deck will be constructed so as to extend outwardly from the outermost beam or girder in cantilever fashion. Of course this overhanging or cantilevered portion of the bridge deck must be properly supported from below by formwork so as to support the uncured concrete. 
     Typically, the temporary support of uncured concrete is achieved by first individually constructing a number of cantilevered support members. These cantilevered support members are then attached to the outermost beam or girder in outwardly extending fashion. Next, a number of longitudinal supports, most typically wooden members, are placed across the cantilevered supports in a direction parallel to the beam or girder. The formwork is then constructed on top of the wooden members. 
     After the concrete has been poured and is adequately cured, the form system and the supporting members are disassembled one-by-one. Such a conventional approach is very labor intensive, time consuming, and expensive both before and after the concrete has been poured. 
     It would be desirable to extend the cost savings afforded by modular construction of wall forms to the modular construction of overhang supports systems. Preferably, such a modular or ganged overhang forming system would permit the placement and/or removal of the system in discrete segments, such as by using a crane. Such modular or ganged construction of concrete overhangs would greatly improve the efficiencies associated with the construction of such overhang systems. 
     SUMMARY OF THE INVENTION 
     A ganged overhang form system constructed in accordance with the teachings of the present invention permits the placement and removal of overhang forms in ganged or modular sections. In the disclosed embodiment, such sections may be, for example, up to twenty four feet (24′) in length. Longer and shorter sections may be contemplated. In the disclosed embodiment, each section may typically include a pair of frames, each of which may be secured by a hanger to a support structure, such as a bridge girder on a bridge under construction. The section will include a form panel already in place and spanning the distance between the frames. Each section may further include, by way of example and not limitation, at least one of the following: 1) edge forms, with or without optional plates for forming drip strips in the edge of the concrete; 2) guardrail attachments; 3) cross-bracing; and/or 4) supporting legs. Once the ganged form sections are assembled, the sections may be placed and removed using a “C” hook without disassembly, thus offering tremendous cost savings compared to more conventional approaches. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an end elevational view of an overhang form section assembled in accordance with the teachings of the present invention with the view being taken through a longitudinally extending concrete bridge girder shown in cross-section; 
     FIG. 2 is an enlarged elevational view taken about the circumscribed portion of FIG.  1  and illustrating certain details of the adjustable connection for use in joining the overhang form section to the bridge girder; 
     FIG. 3 is an elevational view of the adjustable connection taken along line  3 — 3  of FIG. 2; 
     FIG. 4 is an enlarged fragmentary view taken about the circumscribed portion of FIG.  1  and illustrating an adjuster mechanism; 
     FIG. 5 is an enlarged view of the threaded rod for use with the adjustable connection of FIG. 2; 
     FIG. 6 is an enlarged elevational view of an alternative form for the adjustable connection shown in FIG. 2; 
     FIG. 7 is an elevational view taken along line  7 — 7  of FIG. 6; 
     FIG. 8 is a plan view of a form panel for attachment between a pair of supporting frames; 
     FIG. 9 is an end view taken along line  9 — 9  of FIG. 8; 
     FIG. 10 is an end elevational view of an overhanging form section similar to that shown in FIG. 1, but illustrating the overhanging form system attached to a longitudinally extending steel bridge girder shown in cross-section; 
     FIG. 11 is an end elevational view of an overhanging form section similar to that shown in FIG. 1, but illustrating the overhanging form system attached to another form of a concrete bridge girder; 
     FIG. 12 is a bottom plan view of an edge form which is adapted for attachment to the form panel; 
     FIG. 13 is an elevational view thereof; 
     FIG. 14 is a fragmentary elevational view illustrating cross bracing extending between adjacent frames; and 
     FIG. 15 is another fragmentary elevational view but illustrating cross braced guard rail supports as well as cross bracing between adjacent frames; 
     FIG. 16 is an enlarged fragmentary elevational view illustrating one component of the adjustable connection attached to the concrete bridge girder; 
     FIG. 17 is a side elevational view taken along line  17 — 17  of FIG. 16; 
     FIG. 18 is an enlarged fragmentary elevational view similar to FIG. 16 but illustrating an alternative detail for attachment to the concrete bridge girder; 
     FIG. 19 is an enlarged fragmentary elevational view similar to FIG.  10  and illustrating an alternate detail for attachment of the hanger to the top flange of the steel bridge girder; 
     FIG. 20 is a side elevational view of an overhanging concrete form system assembled in accordance with the teachings of the present invention and including cross bracing and guardrail supports attached thereto, with at least some of the guard rail supports extending downwardly to a point roughly level with a lower portion of the frame sections; 
     FIG. 21 is a fragmentary end elevational view illustrating guardrail bracing; 
     FIG. 22A is an enlarged fragmentary top plan view of the inner end of the lower leg of the frame sections illustrating the detail at the point of abutment between the frame sections and the bridge girder; 
     FIG. 22B is an enlarged fragmentary view elevational view of the inner end of the lower leg illustrated in FIG. 22A; 
     FIG. 23A is a fragmentary elevational view of a brace leg that braces the upper leg and the lower leg of the frame sections; 
     FIG. 23B is a side elevational view thereof; 
     FIG. 23C is a cross-sectional view taken along line  23 C— 23 C of FIG. 23B; 
     FIG. 24 is an enlarged fragmentary elevational view of an edge form with an attached cradle assembly; 
     FIG. 25 is a fragmentary elevational view of a crane supported “C” hook engaging a section of an overhanging form section of the present invention; 
     FIG. 26 is an enlarged fragmentary elevational view taken along line  26 — 26  of FIG.  25  and illustrating an attachment member for use in attaching the “C” hook to the form section; 
     FIG. 27 is an elevational view of a drift pin for use with the assembly for attaching the “C” hook to the form section; 
     FIG. 28 is an enlarged fragmentary top plan view illustrating a portion of the assembly for attaching the “C” hook to the form section; 
     FIG. 29 is an enlarged fragmentary view taken about the circumscribed portion of FIG.  25  and illustrating the attachment member attached to an outer portion of the frame section; 
     FIG. 30 is an elevational view taken along line  30 — 30  of FIG.  25  and illustrating further details of the “C” hook; and 
     FIG. 31 is an end elevational view of a fully assembled form section which is standing in a stable configuration on the ground without any external support or bracing means. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following description of the disclosed embodiment is not intended to limit the scope of the invention to the precise form or forms detailed herein. Instead, the following description is intended to be illustrative of the principles of the invention so that others may follow its teachings. 
     Referring now to FIG. 1 of the drawings, an overhanging form system assembled in accordance with the teachings of the present invention is generally referred to by the reference numeral  10 . The overhanging form system  10  is shown attached to a support structure  12 , which extends longitudinally into and out of the plane of the drawing. In the first disclosed embodiment it will be understood that the support structure  12  takes the form of a concrete bridge girder  12 ′ (the concrete bridge girder  12 ′ is shown in FIGS.  1  and  16 - 18 , while another such concrete bridge girder  12 ′″ is shown in FIG.  11 ), or, alternatively, the support structure  12  may take the form of a steel bridge girder  12 ″ (such as is shown in FIGS.  10  and  19 ). The teachings of the disclosed invention may be equally applicable to other forms of support structures. Further, as shown in FIGS. 14,  15  and  20 , it will be appreciated that the overhanging form system  10  will comprise a number of interconnected form sections  10 ′,  10 ″, etc. Only a single form section  10 ′ will be described herein in detail. The form section  10 ′ includes a pair of spaced apart hangers  14 ,  14 ′ and a pair of spaced apart frames  16 ,  16 ′, with an interconnecting panel  38  spanning the distance therebetween. For the sake of brevity, only a single one of the hangers  14  and the frames  16  will described in detail herein. However, it will be understood that the hanger  14 ′ is substantially similar to the hanger  14  and the frame  16 ′ is substantially similar to the frame  16 . 
     Referring again to FIG. 1, the frame  16  is shown connected to the hanger  14 . The frame  16  includes an upper portion  18  supported by the hanger  14  generally adjacent to an upper portion  12   a  of the girder  12 ′, and further includes a lower portion  20  which abuts a lower portion  12   b  of the girder  12 ′. In the disclosed embodiment, the frame  16  is formed by an upper leg  22 , a diagonal leg  24 , and a bracing leg  26 . In the disclosed embodiment, the upper portion  18  of the frame  16  is defined by the upper leg  22  and the lower portion  20  of the frame  16  is defined by the diagonal leg  24 . 
     The upper leg  22  includes an inner end  30   a  and an outer end  30   b . The inner end  30   a  is secured to the hanger  14  at the upper portion  12   a  of the girder  12 ′ by an adjustable connection  32 . The diagonal leg  24  includes an inner end  34   a  and an outer end  34   b  which is connected to the upper leg  22  generally adjacent to the outer end  30   b  of the upper leg  22 . The brace leg  24  includes an upper end  36   a  connected to the upper leg  22  generally adjacent to the inner end  30   a , and a lower end  36   b  connected to the diagonal leg  24  generally adjacent to the inner end  34   a . As shown in FIGS. 1,  14  and  15 , a panel  38  extends between the frames  16  and  16 ′. The panel  38  defines a support surface  38   a  for supporting poured concrete (not shown). As shown in FIGS. 14 and 15, a pair of stiffeners  28   a  and  28   b  extend between the frame  16  and the frame  16 ′. In the disclosed embodiment, the stiffeners  28   a ,  28   b  are attached to the leg  26  on each of the frames  16 ,  16 ′, such as by securing the stiffeners  28   a ,  28   b  to suitable mounting plates  16   c  (FIG.  14 ). Other suitable attachment points may be used. 
     Referring again to FIG. 1, in the disclosed embodiment the diagonal leg  24  and the brace leg  26  are preferably adjustable in length. This adjustability may be accomplished by constructing the legs  24 ,  26  out of telescoping tubular members of different cross sections, using shear pins or bolts to fix the length thereof. The diagonal leg  24  also includes an adjustable connection  40  at the outer end  34   b . The upper end  36   a  of the brace leg  26  and the inner end  30  of the upper leg  22  are connected to a mounting bracket  53  which will be described in detail below. 
     Referring to FIG. 4, in the disclosed embodiment the adjustable connection  40  includes a threaded rod  42  which engages a nut  44  secured to the outer end  34   b  of the diagonal leg  24 , such as by welding. A bolt  42   b  is welded to an end  46  of the threaded rod  42 . The bolt  42   b  extends through an aperture  47  in a diagonal plate  48  connected to the outer end  30   b  of the upper leg  22 , with a shoulder  50  formed at the connection between the threaded rod  42  and the bolt  42   b  bearing against a surface  52  of the plate  48 . Consequently, turning the head of the bolt  42   b  will serve to lengthen the overall length of the diagonal leg  24 , thus altering the angle of the upper leg  22  relative to the horizontal. Alternatively, the threaded rod  42  maybe machined to form a narrowed portion  42   a  beginning at  46  and terminating in a hex head  42   b.  A washer  43  may be provided. 
     Referring now to FIGS. 2 and 3, in the disclosed embodiment the adjustable connection  32  includes the mounting bracket  53 , which includes a pair of upper spaced apart plates  54   a  and a pair of lower spaced apart plates  54   b . A plurality of connection holes  56  may be provided in the upper plates  54   a  (FIG.  2 ), and a plurality of connection holes  57  may be provided in the upper leg  22  (See for example, FIGS.  1  and  10 ), such that the point of connection between the upper leg  22  and the brace leg  26  may be varied. As will be explained below, the mounting bracket  53  is used to secure the frame  16  to the hanger  14  using an elongated threaded rod  17  (FIG.  1  and FIG.  5 ). The threaded rod  17  includes a pair of ends  17   a ,  17   b , with preferably at least one the end  17   a  including a hex head such that the rod  17  is turnable using a wrench. The ends  17   a ,  17   b  may be machined to form the hex heads. The bracket  53  includes a cross member  55 , with the upper plates  54   a  and the lower plates  54   b  mounted to the cross member  55 . Each of the lower plates  54   b  includes an aperture  59 , and a rod  58  is pivotally received in the apertures  59 . The rod  58 , which is preferably hardened steel and includes a tapped hole  63 , is maintained in position between the lower plates  54  by a keeper pin  60  at each end. The cross member  55 , which in the disclosed embodiment is an angled section, includes an elongated hole  61 . The keeper pins  60  limit the rotation of the rod  58  within the apertures  59  by coming into contact with the cross member  55 . Viewing FIG. 3, it will be noted that the keeper pins  60  are spaced away from the plates  54   b , such that the rod  58  is moveable axially through the apertures  59  (i.e., to the left and right when viewing FIG.  3 ). The threaded rod  17  (shown in fragment in FIG. 2) engages the tapped hole  63  in the rod  58 . 
     Referring now to FIGS. 16 and 17, the hanger  14  includes a bracket  15  which is formed by a bent plate  64  having an aperture  66  therethrough and which is mounted to a bearing plate  68  which bears on the upper portion  12   a  of the girder  12 ′. The bent plate  64  is welded or otherwise secured to a rod  69  which is embedded in the concrete girder  12 ′. A nut  65  is provided which engages the threaded rod  17  (viewable in fragment in FIG. 16) so that the frame section  16  may be drawn tightly against the support structure  12 . Further, the adjustable connection  32  is accessible from above by virtue of cutouts provided in the panel  38  (discussed in detail below). Thus, the bracket  15  is connectable to the bracket  53 , thereby permitting the frame  16  to be connected to the girder  12 ′. 
     Referring now to FIGS. 8 and 9, the panel  38  includes an inner edge  72 , an outer edge  74 , and ends  76  and  78 . It will be noted that the end  76  generally overlies and is attached to the frame  16 , while the end  78  generally overlies and is attached to the frame  16 ′. The panel  38  includes a plurality of stiffeners  80  which stiffen the surface  38   a . The panel  38  further includes a plurality of attachment holes  82   a ,  82   b  arranged along two gage lines  84   a ,  84   b . Preferably, threaded nuts (not shown) will be welded to the underside of the panel  38 . A pair of clearance cutouts  86   a ,  86   b  are provided along the inner edge  72 , which cutouts  86   a ,  86   b  provide a clearance passage for the threaded rod  17  as will be explained in greater detail below. 
     The attachment holes  82   a ,  82   b  permit the attachment of an edge form  88 , which is shown in FIGS. 12 and 13. Referring to FIGS. 12 and 13, the edge form  88  includes a pair of attachment plates  90   a ,  90   b , each of which includes a slotted attachment hole  92 . It will be noted that the attachment plates  90   a ,  90   b  are spaced to correspond to the spacing between the gage lines  84   a ,  84   b  on the panel  38 , thus permitting the edge form  88  to be secured to a selected pair of the attachment holes  82   a ,  82   b  on the panel  38 , such as by using bolts through the threaded nuts (not shown) secured to the underside of the panel  38 . It will be appreciated that the slotted holes  92  will permit fine adjustment of the position of the edge form  88 , while the spacing between the attachment holes  82   a ,  82   b  permit larger adjustments. The edge form  88  will preferably include an inner plate  94 , a number of vertically oriented stiffeners  96 , and a plurality of one inch diameter pipe sections  97 . In the disclosed embodiment, the pipe sections  97  are sized to receive a portion of the cradle assembly (discussed below), which in turn supports concrete finishing equipment (not shown). Plate stiffeners or other sections may be used for the stiffeners  96 . 
     Referring now to FIGS. 22A and 22B, the inner end  34   a  of the diagonal leg  24  will preferably include an elongated bar  98  connected to the central portion  100  of the leg  24 . As outlined above, the central portion  100  of the leg  24  is typically a tubular section, such as a 4″×3″×{fraction (3/16)}″ section. Other sizes may be employed based on design considerations as would be known. A bent plate  102  is connected to both the bar  98  and the central portion  100 . A stiffener  104  may be provided. As shown in FIG. 22A, the bar may be longer than the lateral dimension of the central portion  100 , such that the bar  98  will present an elongated surface for abutment with the lower portion  12   b  of the girder  12 ′. 
     Referring now to FIGS. 23A,  23 B and  23 C, the brace leg  26  may alternatively be constructed of a pair of L-shaped sections  26   a ,  26   b , which are attached along the sides of a tubular section  26   c  using a plurality of attachment bolts in a plurality of attachment holes. The L-shaped sections  26   a  and  26   b  may be attached at any one of a plurality of possible positions relative to the section  26   c . This construction offers additional flexibility in adjusting the length of the brace leg  26 , thus making connection of the end  36   b  of the brace leg  26  to the desired point on the diagonal leg  24  easier. 
     Referring now to FIGS. 15,  20  and  21 , a number of posts  106   a ,  106   b  may be secured to the outer edge  74  of the panel  38  using a plurality of bolts  107   a  in selected ones of a plurality attachment holes  107   b  in the outer edge  74  of the panel  38 . The posts  106   a  and  106   b  may be used to support guard rails (not shown). The posts  106   b  extend downwardly below the plane of the panel  38 . It will be noted that one or more braces  108   a  (FIG. 15) and  108   b  (FIG. 21) may be provided in order to brace the posts  106   b  against rotation about two different axes. Each of the posts  106   b  includes a lower end  106   c.    
     Referring now to FIGS. 21,  24  and  25 , a cradle assembly  110  may be secured to the edge form  88  at the desired locations. It will be understood that additional cradle assemblies  110  (not shown) are attached to the edge form  88  at intervals selected by the user. The cradle assembly  110  includes a cradle head  110   a  which is vertically adjustable using an adjustment nut  110   b  which engages a threaded rod  110   c . One or more chamfer strips  112   a ,  112   b  and  112   c  are provided which may be attached to the edge form  88  and which extend generally parallel to the edge form  88 . At least one of the chamfer strips, for example the chamfer strip  112   a , may be placed loosely upon the panel  38 . The chamfer strips  112   a ,  112   b  and  112   c  may function to form chamfered edges or indentations on the concrete section  113  (shown in fragment in FIG. 25) to be poured. One or more stiffener plates  112   d  extending to a base plate  112   e  may also be provided. As would be known, the cradle assembly  110  is used to support concrete finishing equipment that rolls along a rail (not shown) extending between adjacent cradle assemblies  110 . 
     Referring now to FIGS. 25,  30  and  31 , a “C” hook assembly  114  may be used to pick up one section  10 ′ of the overhanging form system  10  from a ground assembly station (for example, as shown in FIG.  31 ), and place the form section  10 ′ adjacent to the girder  12 ′ for connection to the hangers  14 ,  14 ′. In a similar manner, the “C” hook assembly  114  may be used to strip the section  10 ′ off the support structure  12  after the poured concrete has sufficiently cured, and again place the form section  10 ′ on the ground as shown in FIG.  31 . The “C” hook assembly  114  includes a pair of bottom legs  116   a ,  116   b , a pair of top legs  118   a ,  118   b , a pair of vertical legs  119   a ,  119   b , and a plurality of interconnecting members  120  and braces  122 . The vertical legs  119   a ,  119   b  will include holes  119   c  (FIG.  25 ). Attachment plates  124  are provided on each of the top legs  118   a ,  118   b , with each of the attachment plates  124  having a plurality of holes  126 , thus enabling the “C” hook assembly  114  to be lifted by a crane (not shown) using suitable rigging  128 . 
     Referring to FIGS. 25,  26 ,  28  and  29 , a pair of mounting brackets  130  are mounted to the outer edge  74  of the panel  38  by a plurality of suitable fasteners  131 . The mounting brackets  130  are spaced to match the spacing of the vertical legs  119   a ,  119   b  and may be used to secure the “C” hook assembly  114  to the form section to be lifted. Each of the mounting brackets  130  includes a pair of spaced apart plates  132 , each of which includes a pair of holes  134 . Using a pair of pins  136  (FIGS.  27  and  28 ), the “C” hook assembly  114  is connectable to the mounting brackets  130  by inserting pins  136  through the holes  134  in the plates  132  of the mounting brackets  130  and through the holes  119   c  in each of the vertical legs  119   a ,  119   b . Each of the pins will preferably include a tapered end  136   a , an enlarged flange  136   b , and a hole  136   c  for receiving a cotter pin (not shown) to maintain the pin  136  in place. 
     In operation, one form section  10 ′ of the overhanging form system  10  is assembled by connecting the legs  22 ,  24  and  26  to each other as shown in FIG. 1 to create the frame  16 . Again, it will be understood that the frame  16 ′ is assembled in a similar manner. The length of each of the legs  22 ,  24 , and  26  will be varied depending on the dimensions of the particular application. The length of the legs  24  and  26  may be telescoped in the disclosed embodiment. Further, the adjustable connection  40  at the outer ends  30   b ,  34   b  of the legs  22 ,  24 , respectively, is assembled as outlined above. 
     The panel  38  is connected to the upper leg  22  of each of the frames  16 ,  16 ′. The distance between the frames  16 ,  16 ′ will vary depending on the particular application, as will the length of the interconnecting panel  38 . Preferably, the form section  10 ′ will be assembled at an assembly location which is removed from the support structure  12 , such as, for example, on the ground (as shown in FIG.  31 ). As shown in FIGS. 14 and 15, the stiffeners  28   a  and  28   b  are secured to both of the frame  16  and the frame  16 ′. The posts  106   a ,  106   b  are secured to the outer edge  74  of the panel  38  using the bolts  107   a  in the attachment holes  107   b  at the outer edge  74  of the panel  38 . Again, guard rails (not shown) may also be attached. The braces  108   a  (FIG. 15) and  108   b  (FIG. 21) are attached to brace the posts  106   b . The lower end  106   c  of each of the posts  106   b  may cooperate with the ends  36   b  of the legs  24  on each of the frames  16 ,  16 ′ such that the resulting form section  10 ′ may stand unsupported on the ground (FIG.  31 ). The edge form  88  and the cradle assemblies  110  are secured at the appropriate locations as outlined above. 
     When the overhanging form system  10  is used in conjunction with the concrete bridge girder  12 ′, a plurality of the embedded rods  69  will preferably already be in place on the girder  12 ′, spaced at the appropriate intervals. Consequently, the hangers  14 ,  14 ′ and the brackets  15 ,  15 ′ (FIGS. 16 and 17) will already be in place on the girder  12 ′. 
     The form section  10 ′ is placed by securing the “C” hook assembly  114  to the form section  10 ′ as outlined above using the pins  136  inserted through the appropriate holes  134  in the mounting bracket  130  and the holes  119   c  in the legs  119   a ,  119   b . Using the rigging  128 , the form section  10 ′ may be lifted using a conventional crane or other lifting device (not shown). 
     Once the form section  10 ′ is lifted to a position adjacent to the girder  12 ′, the adjustable connection  32  is used to connect the bracket  53  to the bracket  15 , thus securing the frames  16 ,  16 ′ to their respective hangers  14 ,  14 ′. When the section  10 ′ is lifted into place, the rod  17  is fed through the aperture  66  in the bent plate  64 , preferably from above. The cutouts  86   a ,  86   b  in the panel  38  provide clearance for the threaded rods  17 . Each rod  17  extends through the elongated hole  61  in the cross member  55  and engages the tapped hole  63  in the rod  58 . Rotation of the rod  58  about its longitudinal axis within the apertures  59  accounts for angular variations. Further, the elongated hole  61  in the cross member  55 , along with the play permitted by the keeper pins  60 , account for slight longitudinal misalignments. Adjustment of the frame section  16  relative to the upper portion  12   a  of the girder  12 ′ is accomplished by rotating the nut  65  that engages the rod  17 , thus drawing the frame section  16  toward or away from the hanger  14  depending on the direction of rotation of the nut  65 . Alternatively, the adjustment of the frame section  16  may also be accomplished by rotating the entire rod  17  using a wrench attached to the hex heads at the ends  17   a  or  17   b . Either way, adjustment of the connection  32  is effectuated. 
     As outlined above, the elevation of the outer end  30   b  of the upper leg  22  may be accomplished using the adjustable connection  40  (FIG. 4) at the intersection of the upper leg  22  and the diagonal leg  24  as discussed in detail above. Preferably, the threaded rod  17  will be encased in a suitable sleeve  138  (indicated by dotted lines in FIG.  1 ). Accordingly, subsequent to the concrete pour, the threaded rod  17  may be removed from above (or below) using a suitable tool engaging the hex head at the and  17   a . The remaining hole may be filled by grout or other suitable material. 
     Referring now to FIGS. 6 and 7, an alternate embodiment for a bracket used in the adjustable connection  32  is shown which is referred to by the reference numeral  253 , and which may be substituted for the bracket  53  shown in FIGS. 2 and 3 in order to secure the frame  16  to the hanger  14 . The bracket  253  includes a cross member  255 . A pair of upper plates  254   a  and a pair of lower plates  254   b  are mounted to the cross member  255 . As shown in FIG. 6, the cross member  255  includes pair of angled capture plates  255   a ,  255   b  and an elongated hole  260 . A threaded plate  259 , which may be a plate with a nut welded thereon, is loosely disposed between the capture plates  255   a ,  255   b  and the cross member  255 . As shown in FIG. 7, the lower plates  254   b  prevent the plate  259  from sliding out past the ends of the capture plates  255   a ,  255   b . Also viewing FIG. 7, it will be noted that the plate  259  is moveable left to right (i.e., in a direction parallel to an axis of the girder  12 ′) in a direction parallel to the elongated hole  260 . The threaded rod  17  discussed above with respect to the first embodiment engages the threaded plate  259 , so that the bracket  253  may be connected to the bracket  15  in a manner similar to that outlined above with respect to FIGS. 2 and 3. 
     Referring now to FIG. 18, an alternate form for the hanger and the bracket are shown which are referred to by the reference numerals  214  and  215 , respectively. The hanger  214  and the bracket  215  may be used when the embedded rod  69  shown in FIGS. 1,  16  and  17  is either missing, or has been misplaced longitudinally along the girder  12 ′. The bracket  215  includes a pair of bent plates  264   a  and  264   b , each of which defines a through hole  266   a ,  266   b . The bent plates  264   a  and  264   b  are connected by a rod  265 . A threaded rod  269  may be embedded in the upper portion  12   a  of the girder  12 ′ by drilling a hole at the needed location and grouting the rod  269  in place. The bent plate  264   a  is secured to the grouted in place rod  269  using a threaded nut  267 . The threaded rod  17  (not shown in FIG. 18) is then connected to the bracket  53  attached to the appropriate frame section  16  and adjusted as necessary in the manner described above with respect to the first described embodiment. 
     Referring now to FIGS. 10,  11  and  19 , the overhanging form system  10  in accordance with the present invention is also useable with other forms of support structure  12 , such as a steel “I” beam or wide flange girder  12 ″ (FIGS. 10 and 19) or another concrete girder  12 ′″ (FIG.  11 ). In such applications, certain details of the hangers and brackets are modified. In the embodiment shown in FIGS. 10 and 19, a hanger  214  includes a bracket  215  which is formed by a bent plate  264  having an aperture  266  therethrough and which is connected by a rod  270  to a J-shaped bracket  269  which engages the top flange  212   a  of the girder  12 ″. The J-shaped bracket  269  can be secured at a desired location along the girder  12 ″ simply by hooking the J-shaped bracket over the top flange of the girder  12 ″. Alternatively, referring to FIG. 11, the J-shaped bracket  269  may include a bolt  271   a  and a threaded nut  271   b , with the J-shaped bracket  269  being secured to the top flange of the girder  12 ″ by tightening the nut  271   b . Either way may be used to secure the hanger  14  to the support structure  12  by inserting the rod  17  through the aperture  266  and into the bracket  53  (discussed above with respect to the first described embodiment), thereby permitting the frame  16  of the frame section  10 ′ to be connected to the girder  12 ″. 
     In the embodiment shown in FIG. 11, the relative lengths and angles of the legs  22 ,  24 , and  26  are adjusted such that the top leg  22  (and the attached panel  38 ) are disposed at the proper elevation and angle. 
     It will further be appreciated that in accordance with the disclosed embodiment numerous form sections may be secured to the support structure adjacent to each other to form a generally continuous overhanging form system. The adjacent sections need not be connected to each other, and thus each form section, including all desired attached components such as edge forms, guard rails, etc., may be set and stripped with a minimum of labor. 
     The aforementioned hanger details may be substituted for each other. For example, on certain jobs it may be desired to attach the hangers to cast in place embedded rods, while in other applications it may be desirable to drill and grout the rods individually. Similarly, the J-shaped brackets  269  of FIGS. 10 and 19 are interchangeable as desired. 
     In accordance with the disclosed embodiment, it will be noted that the overhanging form system  10  may be assembled, placed on the girder, and removed from the girder all without requiring personnel to work underneath the form system. Because the adjustable connections  32  are easy to align and are accessible from above, each of the remotely assembled form sections may be secured to the appropriate hangers on the girder without requiring personnel to work underneath a partially secured form section. The safety offered by such a system is especially evident on high bridges and other structures. Further, safety features such as guardrail posts, handrails, and toeboards may be secured to the sections and left in place throughout the job, with no need to repeatedly assemble and disassemble such items. 
     Those skilled in the art will appreciate that, although the teachings of the invention have been illustrated in connection with certain embodiments, there is no intent to limit the invention to such embodiments. On the contrary, the intention of this application is to cover all modifications and embodiments fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.

Technology Category: 0