A self-bracing, two-way moment frame precast system for industrial support structure and method of erecting a precast industrial support structure without temporary or permanent bracing or shoring are disclosed. This is accomplished by utilizing a moment frame element in two directions to create free standing tower that requires no bracing during erection or in service. The system also utilizes a connection that allows the erection crane to achieve alignment during erection such that the entire system can be erected by a ground based personnel.

CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 62/057,753, filed Sep. 30, 2014. The above patent application is incorporated herein by reference in its entirety to provide continuity of disclosure. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates generally to industrial construction, and is particularly concerned with a precast industrial support structure. 
       BACKGROUND OF THE INVENTION 
       [0003]    Currently, much of the cost and time related to support industrial structures during erection is for a temporary or permanent bracing or shoring in a transverse direction to achieve lateral stability. Those structures still utilize bracing (permanent or temporary) in the longitudinal direction as well for stability in that axis. The temporary bracing must be then removed after all structural connections are established. There is also cost and danger involved in having builders work on temporary bracing or shoring, and for the cost of a crane to lift additional construction material up to the builders. 
         [0004]    Another consideration related to erecting the structure is the ease and effectiveness with which such structures may be erected with simple utilization of the crane and no additional man power at the work site. One task which adds to the time, safety, complexity and cost of constructions is having additional members of a construction crew to assist the crane operator in aligning the connection of the construction. 
         [0005]    Accordingly, a need exists for a system and method of erecting an industrial structure to avoid costs related to temporary and permanent bracing or shoring. With a novel two-way, self-bracing and aligning system, any additional man power and cost is eliminated. 
       SUMMARY 
       [0006]    A self-bracing and self-aligning, two-way moment frame precast system for industrial support structures is disclosed. A method of erecting a pre-cast industrial support structure without temporary or permanent bracing or shoring in the longitudinal and transverse directions for lateral stability is further disclosed that utilizes a set of moment frame members in two directions to create a free-standing structure that requires no bracing during erection or in service. 
         [0007]    A two-way moment frame member includes a beam, a set of connector portions attached to the beam, a male connector that includes a collapsible stabilizer attached to each connector portion, and a set of rebars attached to each connector portion and adjacent to the collapsible stabilizer. A female connector positioned opposite the male connector includes a stabilizer receiver attached to each connector portion, and a set of sleeves attached to each connector portion and adjacent to the stabilizer receiver. 
         [0008]    A connection system for a two-way moment frame member including a stabilizer receiver, a set of sleeves adjacent to the stabilizer receiver, a collapsible stabilizer sized to at least partially collapse when engaged with the stabilizer receiver, a slot integrally formed in the collapsible stabilizer, and a set of rebars adjacent to the collapsible stabilizer. 
         [0009]    A free-standing two-way moment support structure includes a base structure, a set of moment frame members connected to the base structure, each moment frame member includes a beam, a set of connector portions attached to the beam, a collapsible stabilizer attached to each connector portion, a set of rebars attached to each connector portion and adjacent to the collapsible stabilizer, a stabilizer receiver integrally formed in each connector portion opposite the collapsible stabilizer, and a set of sleeves integrally formed in each connection portion opposite the set of rebars. 
         [0010]    In particular, according to one embodiment of the present invention, the slotted stabilizer at least partially collapses in the stabilizer receiver and causes a friction fit between the stabilizer and the stabilizer receiver to eliminate the need for temporary bracing by providing stability during erection. 
         [0011]    The disclosed embodiments provide a self-bracing, self-aligning, two-way moment frame precast system for an industrial support structure which is very competitive from a mere economic standpoint. More importantly, combination of a self-aligning alignment pin connection with remote crane release devices eliminates engaging personnel at high elevation and substantially improves in erection safety as it allows such alignment to be performed in the air. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    In the detailed description below, reference will be made to the following drawings. 
           [0013]      FIG. 1  is a perspective view of a male connector and a female connector of a connection system of one embodiment. 
           [0014]      FIG. 2  is a front view of the male connector of one embodiment. 
           [0015]      FIG. 3  is a side view of the male connector of one embodiment. 
           [0016]      FIG. 4  is a detail section view of the female connector of one embodiment. 
           [0017]      FIGS. 5A ,  5 B, and  5 C show a top view, a front view, and a side view, respectively, of a moment frame member of one embodiment. 
           [0018]      FIG. 6  is a perspective view of a male connector and a female connector of a connection system of another embodiment. 
           [0019]      FIG. 7  is a front view of the male connector of another embodiment. 
           [0020]      FIG. 8  is a side view of the male connector of another embodiment. 
           [0021]      FIG. 9  is a detail section view of a female connector of another embodiment. 
           [0022]      FIGS. 10A ,  10 B, and  10 C show a top view, a front view, and a side view, respectively, of a moment frame member of another embodiment. 
           [0023]      FIG. 11A  is a flowchart of a method for assembling a support structure. 
           [0024]      FIG. 11B  is a perspective view of a base structure. 
           [0025]      FIG. 11C  is a perspective view of a first set of moment members connected to the base structure. 
           [0026]      FIG. 11D  is a perspective view of a second set of moment frame members connected to the first set of moment frame members and the first set of moment frame members connected to the base structure. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    Referring to  FIG. 1  in one embodiment, connection system  100  includes male connector  101  and female connector  102 . Male connector  101  includes stabilizer  105  attached to moment frame member  103  and a set of rebars  106 ,  107 ,  108 , and  109  attached to moment frame member  103  and adjacent to stabilizer  105 . Moment frame member  103  includes beam portion  119  and connector portion  120 . In a preferred embodiment, beam portion  119  extends generally along the x-axis and connector portion  120  extends generally along the z-axis. In a preferred embodiment, beam portion  119  and connector portion  120  are generally perpendicular with respect to each other. Other angles may be employed. In a preferred embodiment, stabilizer  105  includes slot  116  integrally formed therein and extends in a generally longitudinal direction along stabilizer  105 . 
         [0028]    Female connector  102  includes stabilizer receiver  110  and a set of sleeves  112 ,  113 ,  114  and  115 , integrally formed in moment frame member  104 . Each of set of sleeves  112 ,  113 ,  114 , and  115  is sized to accommodate set of rebars  106 ,  107 ,  108 , and  109 , respectively. Stabilizer receiver  110  includes taper  111 . Moment frame member  104  includes beam portion  117  and connector portion  118 . In a preferred embodiment, beam portion  117  extends generally along the y-axis and connector portion  118  extends generally along the z-axis. In a preferred embodiment, beam portion  117  and connector portion  118  are generally perpendicular with respect to each other. 
         [0029]    In a preferred embodiment, each of moment frame members  103  and  104  is made of concrete, preferably pre-cast concrete. Other materials may be employed. 
         [0030]    In a preferred embodiment, stabilizer  105  is a generally cylindrical hollow tube. Other shapes may be employed. 
         [0031]    In a preferred embodiment, stabilizer  105  is made of a durable material such as a metal or metal alloy. Other materials known in the art, such as plastics may be employed. 
         [0032]    In a preferred embodiment, each of set of rebars  106 ,  107 ,  108 , and  109  is made of a durable and rigid material such as steel. Other suitable materials known in the art may be employed. 
         [0033]    In a preferred embodiment, each of set of rebars  106 ,  107 ,  108 , and  109 , is cast-in or drilled and grouted into moment frame member  103 . Other means of attachment known in the art may be employed. 
         [0034]    In a preferred embodiment, stabilizer receiver  110  has a generally frustoconical shape. Other shapes, such as generally cylindrical, may be employed. 
         [0035]    In a preferred embodiment, stabilizer receiver  110  and taper  111  are pre-cast formed into moment frame member  104 . In another embodiment, stabilizer receiver  110  and taper  111  are cut, drilled, and/or machined into moment frame member  104 . Other means for attachment may be employed. 
         [0036]    In a preferred embodiment, set of sleeves  112 ,  113 ,  114 , and  115 , is cast-in or drilled and grouted into pre-cast element  104 . In other embodiments, set of sleeves  112 ,  113 ,  114 , and  115 , are pre-cast into moment frame member  104 . Other means of attachment known in the art may be employed. 
         [0037]    In use, male connector  101  is received into female connector  102 . Stabilizer  105  inserts into stabilizer receiver  110  and each of the set of rebars  106 ,  107 ,  108 , and  109 , insert into sleeves  112 ,  113 ,  114 , and  115 , respectively. Stabilizer  105  is at least partially collapsed via slot  116  as it engages with stabilizer receiver  110 , thereby enabling a frictional fit between male connector  101  and female connector  102  and eliminating a need for temporary bracing. As can be seen, connection system  100  substantially reduces or eliminates a first moment about the x-axis and a second moment about the y-axis, thereby eliminating a need for temporary bracing along the x-axis and the y-axis when compared to the prior art. 
         [0038]    Referring to  FIGS. 2 and 3 , stabilizer  105  extends into moment frame member  103  beyond surface  121  of moment frame member  103 . Slot  116  of stabilizer  105  extends along a generally longitudinal direction of stabilizer  105  to generally abut surface  121 . In other embodiments, slot  116  extends to a position adjacent to surface  121 . 
         [0039]    Referring to  FIG. 4 , stabilizer receiver  110  is integrally formed in moment frame member  104 . Taper  111  is adjacent to surface  122  of moment frame member  104  and adjacent to receiver  110 . Sleeves  114  and  115  extend into pre-cast element  104  beyond surface  122 . Stabilizer receiver  110  further includes end surface  123  and opening  124 . Opening  124  has diameter d 1  and end surface has diameter d 2 . 
         [0040]    In a preferred embodiment, diameter d 2  is less than diameter d 1 . In another embodiment, diameter d 2  is approximately equal to diameter d 1 . 
         [0041]    In a preferred embodiment, d 1  is less than the diameter of stabilizer  105 . 
         [0042]    In a preferred embodiment, taper  111  has a generally flat surface surrounding stabilizer receiver  110 . In another embodiment, taper  111  has a curved surface. Other shapes may be employed. 
         [0043]    In a preferred embodiment, taper  111  provides a generally chamfered surface to enable a better fit and connection for stabilizer receiver  110 . 
         [0044]    Referring to  FIGS. 5A ,  5 B, and  5 C, moment frame member  500  includes beam  501  and connector portions  502  and  503  attached to beam  501 . Each of connector portions  502  and  503  includes male connector  101  and female connector  102 . Male connector  101  is positioned opposite female connector  102 . In this way, a set of moment frame members  500  is stacked and/or positioned generally perpendicular with respect to each other to modularly assemble a pre-cast structure, as will be further described below. 
         [0045]    Referring to  FIG. 6  in another embodiment, connection system  600  includes male connector  601  and female connector  602 . Male connector  601  is attached to moment frame member  603  and includes stabilizer  605  attached to moment frame member  603  and a set of rebars  606 ,  607 ,  608 , and  609  attached to moment frame member  603 . Moment frame member  603  includes beam portion  622  and connector portion  623 . Beam portion  622  extends generally along the x-axis and connector portion  623  extends generally along the z-axis. In a preferred embodiment, beam portion  622  and connector portion  623  are generally perpendicular with respect to each other. Other angles may be employed. Stabilizer  605  includes slot  621 , integrally formed therein and extends in a generally longitudinal direction along stabilizer  605 . Stabilizer  605  further includes notch  610  integrally formed therein. 
         [0046]    Female connector  602  includes stabilizer receiver  611  and set of sleeves  614 ,  615 ,  616 , and  617 , integrally formed into moment frame member  604 . Each of set of sleeves  614 ,  615 ,  616 , and  617  is sized to accommodate set of rebars  606 ,  607 ,  608 , and  609 , respectively. Moment frame member  604  includes beam portion  624  extending generally along the y-axis and connector portion  625  extending generally along the z-axis. 
         [0047]    In one embodiment, stabilizer receiver  611  includes stabilizer pin  613  connected to stabilizer receiver  611 . 
         [0048]    In a preferred embodiment, each of moment frame members  603  and  604  is made of concrete, preferably pre-cast concrete. Other materials may be employed. 
         [0049]    In a preferred embodiment, stabilizer  605  is made of a durable material such as a metal or a metal alloy. In a preferred embodiment, stabilizer  605  is a hollow generally cylindrical tube. Other materials and shapes known in the art may be employed. 
         [0050]    In a preferred embodiment, each of set of rebars  606 ,  607 ,  608 , and  609  are made of a durable and rigid material such as steel. Other suitable materials known in the art may be employed. 
         [0051]    In a preferred embodiment, each of stabilizer  605  and set of rebars  606 ,  607 ,  608 , and  609  is cast-in or drilled and grouted into moment frame member  603 . Other means for attachment known in the art may be employed. 
         [0052]    In a preferred embodiment, each of stabilizer receiver  611  and set of sleeves  614 ,  615 ,  616 , and  617  is cast-in or drilled and grouted into moment frame member  604 . Other means for attachment such as cutting, drilling, and/or machining known in the art may be employed. 
         [0053]    In a preferred embodiment, stabilizer receiver  611  has a generally frustoconical shape. Other shapes may be employed. 
         [0054]    In a preferred embodiment, stabilizer pin  613  is made of a durable and rigid material such as steel. In another embodiment, stabilizer is made of concrete, preferably pre-cast concrete. Other suitable materials may be employed. 
         [0055]    In a preferred embodiment, stabilizer pin  613  is cast-in or drilled and grouted into moment frame member  604 . Other means for attachment known in the art may be employed. 
         [0056]    In use, stabilizer  605  is inserted into stabilizer receiver  611  and stabilizer pin  613  is inserted into stabilizer  605 . Stabilizer  605  at least partially collapses via slot  621  upon engagement with stabilizer receiver  611  to provide a frictional fit between stabilizer  605  and stabilizer receiver  611 . Notch  610  provides an opening to more easily insert stabilizer pin  613  into stabilizer  606 , for example, lateral movement of stabilizer pin  613 . Likewise, set of rebars  606 ,  607 ,  608 , and  609 , is inserted into sleeves  614 ,  615 ,  616 , and  617 , respectively. As can be seen, connection system  600  substantially reduces and/or prevents movement in the form of a moment about the y-axis and a moment about the x-axis, thereby eliminating the need for temporary and/or permanent bracing along the x-axis and/or the y-axis when compared to the prior art. 
         [0057]    Referring to  FIGS. 7 and 8 , notch  610  of stabilizer  605  includes edges  618  and  620 , connected to each other by transition  619 . In a preferred embodiment, transition  619  is generally curved. In another embodiment, transition  619  is a point, thereby edges  618  and  620  meet at a corner. 
         [0058]    Stabilizer  605  extends into moment frame member  603  beyond surface  626  of moment frame member  603 . Slot  621  of stabilizer  605  extends in a generally longitudinal direction along stabilizer  605  to generally abut surface  626 . In other embodiments, slot  621  extends to a position adjacent to surface  626 . In a preferred embodiment, edge  618  defines a generally diametrical plane that generally aligns with axis  629  of stabilizer  605 . 
         [0059]    Referring to  FIG. 9 , stabilizer receiver  611  includes taper  612  adjacent to surface  628  of moment frame member  604  and to stabilizer receiver  611 . Stabilizer receiver  611  further includes opening  630  and end surface  627 . Opening  630  has diameter d 3  and end surface  627  has diameter d 4 . In a preferred embodiment, diameter d 4  is less than diameter d 3 . In another embodiment, diameter d 4  is approximately equal to diameter d 3 . In a preferred embodiment, stabilizer  613  inserts into pre-cast element  604  beyond end surface  627 . In another embodiment, stabilizer pin  613  is attached to end surface  627 . Stabilizer pin  613  is generally concentrically aligned with receiver  611  and extends from moment frame member  604  beyond surface  628 . 
         [0060]    In a preferred embodiment, stabilizer pin  617  has a diameter less than stabilizer  605 . 
         [0061]    In a preferred embodiment, stabilizer receiver  611  has a generally frustoconical shape. Other shapes such as generally cylindrical known in the art may be employed. 
         [0062]    In a preferred embodiment, taper  612  has a generally flat surface surrounding stabilizer receiver  611 . Other shapes, such as a rounded corner may be employed. In a preferred embodiment, taper  612  provides a chamfered surface to stabilizer receiver  611 . 
         [0063]    Referring to  FIGS. 10A ,  10 B and  10 C, moment frame member  1000  includes beam portion  1001  and connector portions  1002  and  1003 . Each of connector portions  1002  and  1003  includes male connector  601  and female connector  602 . Male connector  601  and female connector  602  are arranged generally opposite with respect to each other. 
         [0064]    In this way, a set of moment frame members  1000  is stacked and/or positioned generally perpendicular with respect to each other to provide a modular connection arrangement for the set of moment frame members  1000  as will be further described below. As will be appreciated by those skilled in the art, moment frame member  1000  having connector portions  1002  and  1003  provide a pre-cast modular building product to build modular concrete structures in a more efficient manner than that of the prior art. 
         [0065]    Referring to  FIGS. 11A ,  11 B,  11 C and  11 D, a method for connecting a set of moment frame members is described. Referring to  FIG. 11A , at step  1101 , a base structure is provided. In a preferred embodiment, the base structure is a set of generally vertical pre-cast concrete columns. In other embodiments, any type of base structure known in the art may be employed. At step  1102 , a first set of moment frame members is connected to the base structure. At step  1103  a second set of moment frame members is connected to the first set of moment members. In a preferred embodiment, the second set of moment members are positioned generally perpendicularly with respect to the first set of moment members. 
         [0066]    In a preferred embodiment, each of the first set of moment members and the second set of moment members has a connection system as previously described in connection systems  100  and/or  600 . It will be appreciated by those skilled in the art that the disclosed method provides a modular construction and assembly of a pre-cast structure, without the need for external bracing. 
         [0067]    Referring to  FIG. 11B , base structure  1104  includes columns  1105 ,  1106 ,  1107 , and  1108 . Column  1105  includes male connector  1109 . Column  1106  includes male connector  1110 . Column  1107  includes male connector  1111 . Column  1108  includes male connector  1112 . 
         [0068]    Referring to the  FIG. 11C , moment frame members  1113  and  1114  are connected to base structure  1104 . Moment frame member  1113  includes beam  1118  and connector portions  1119  and  1120 . Connector portion  1119  includes male connector  1127  and female connector  1123  opposite male connector  1127 . Connector portion  1120  includes female connector  1124  and male connector  1128  opposite female connector  1124 . Moment frame member  1113  is connected to vertical columns  1105  and  1106  using female connectors  1123  and  1124  as previously described in connection systems  100  and/or  600 . Moment frame member  1114  includes beam  1115  and connector portions  1116  and  1117 . Connector portion  1116  includes female connector  1121  and male connector  1125  opposite female connector  1121 . Connector portion  1117  includes female connector  1122  and male connector  1126  opposite female connector  1122 . Moment frame member  1114  is connected to vertical columns  1107  and  1108  with female connectors  1121  and  1122  as previously described in connection systems  100  and/or  600 . 
         [0069]    Referring to  FIG. 11D , moment frame members  1129  and  1130  are connected to moment frame members  1114  and  1113 . Moment frame members  1129  and  1130  are substantially the same as moment frame members  1113  and  1114 . 
         [0070]    As can be seen, moment members  1113  and  1114  are generally aligned along the y-axis and moment frame members  1129  and  1130  are generally aligned along the x-axis, thereby providing a transverse connection system. As can further be seen, the connection systems of the disclosed embodiments provide two-way moment bracing generally along the x-axis and the y-axis. Further, the connection of these disclosed embodiments eliminate the need for external bracing along the x-axis and the y-axis, and enable the assembly of a free-standing structure. 
         [0071]    It will be appreciated that the invention is not restricted to the particular embodiment that has been described, and that variations may be made therein without departing from the scope of the invention as defined in the appended claims, as interpreted in accordance with principles of prevailing law, including the doctrine of equivalents or any other principle that enlarges the enforceable scope of a claim beyond its literal scope. Unless the context indicates otherwise, a reference in a claim to the number of instances of an element, be it a reference to one instance or more than one instance, requires at least the stated number of instances of the element but is not intended to exclude from the scope of the claim a structure or method having more instances of that element than stated. The word “comprise ” or a derivative thereof, when used in a claim, is used in a nonexclusive sense that is not intended to exclude the presence of other elements or steps in acclaimed structure or method.