A three-dimensional jacket-plate connector connects at least two members. Each member comprises wide-flanged steel I-beam section. The jacket-plate connector comprises first and second three-dimensional jacket plates.

CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority as a continuation-in-part to U.S. patent application Ser. No. 12/804,602, filed on Apr. 19, 2010, entitled BOLTED STEEL CONNECTIONS WITH 3-D JACKET PLATES AND TENSION RODS, by WeiHong Yang, the contents of which are hereby incorporated by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally, to construction material, and more specifically, to a steel jacket plate connector. 
     BACKGROUND 
     During construction of steel frames and trusses, individual members such as beams and columns are connected together to form a structure. Conventionally, two-dimensional gusset plates are used to connect steel members with either welding or bolts, or their combinations. 
     However, connecting steel beams requires a degree of physical fitness and expertise that can make it a difficult job. Typically, each connection is custom fit on site while steel members are held in place. The labor cost of welders assembling connectors on site can be prohibitive. Moreover, the time to construct a structure is lengthened by the connections because adjacent members cannot be added until a supporting member is secured. 
     What is needed is a technique to allow faster and lower cost installation of connections. 
     SUMMARY OF THE INVENTION 
     The above needs are met by an apparatus, system, method and method of manufacture for a three-dimensional jacket-plate connector. 
     In one embodiment, the 3-D connector comprises first three-dimensional jacket plate. A second three-dimension jacket plate that is a mirror image of the first three-dimensional jacket plate. The two jacket plates are bolted to opposite sides of a joint of the steel I-beam members. 
     In another embodiment, a jacket plate comprises a primary c-channel welded to a connecting c-channel that intersect to match angles of the joint formed by a primary I-beam member and a connecting I-beam member. 
     Advantageously, the 3-D jacket connection can achieve exceptional structural performance, including higher strength and ductility, stronger yet simpler connections, higher quality, small components for easy storage and transportation. It also provides easy installation to increase the speed and reduce the price of erecting steel structures. The 3-D jacket connection addresses all possible connection type in such a simple and yet consistent manner that it is practically a versatile connections system that can be use in any steel frames and trusses that is made of wide-flanged steel I-beam sections. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       In the following drawings like reference numbers are used to refer to like elements. Although the following figures depict various examples of the invention, the invention is not limited to the examples depicted in the figures. 
         FIGS. 1A-E  are schematic diagrams illustrating steel frames, according to some embodiments. 
         FIGS. 2A-D  are schematic diagrams illustrating steel trusses, according to some embodiments. 
         FIGS. 3A-B  are schematic diagrams illustrating a moment connection at a top floor, corner condition, of the steel frame of  FIG. 1A , according to some embodiments. 
         FIGS. 4A-B  are schematic diagrams illustrating a moment connection at an intermediate floor, side condition, of the steel frame of  FIG. 1A , according to some embodiments. 
         FIGS. 5A-B  are schematic diagrams of a moment connection at a top floor, interior bay condition, of the steel frame of  FIG. 1A , according to some embodiments. 
         FIGS. 6A-B  are schematic diagrams illustrating a moment connection at an intermediate floor, interior bay condition, of the steel frame of  FIG. 1A , according to some embodiments. 
         FIGS. 7A-D  are schematic diagrams illustrating a moment connection of an eccentrically braced frame (EBF), of the steel frame of  FIG. 1B , according to some embodiments. 
         FIGS. 8A-D  are schematic diagrams illustrating a moment connection of special concentrically braced frame (SCBF), of the steel frame of  FIG. 1C , and the similar connections of the steel truss of  FIG. 2D , according to some embodiments. 
         FIGS. 9A-D  are schematic diagrams illustrating a moment connection of an EBF and an inverted V SCBF, brace and beam to column connection, of the steel frame of  FIG. 1D , and the similar connections of the steel truss of  FIG. 2C , according to some embodiments. 
         FIGS. 10A-D  are schematic diagrams illustrating a moment connection of an EBF and an inverted V SCBF, brace and column connection at a foundation, of the steel frame of  FIG. 1B , according to one embodiment. 
         FIGS. 11A-D  are schematic diagrams illustrating a moment connection of an SCBF, braces and beam to column connection at a floor, of the steel frame of  FIG. 1D , according to one embodiment. 
         FIGS. 12A-F  are schematic diagrams illustrating a moment connection of an SCBF, brace and beam to column connection at a top floor, of the steel frame of  FIG. 1E , according to some embodiments. 
         FIGS. 13A-B  are schematic diagrams illustrating a moment connection of an SCBF, brace and beam crossing connection, of the steel frame of  FIG. 1D , according to some embodiments. 
         FIGS. 14A-C  are schematic diagrams illustrating a moment connection of an SCBF, brace crossing connection without beam condition, of the steel frame of  FIG. 1E , according to some embodiments. 
         FIGS. 15A-C  are schematic diagrams illustrating a Vierendeel truss, connection condition, of the steel truss of  FIG. 2A , according to one embodiment. 
         FIGS. 16A-B , are schematic diagrams illustrating a steel bridge truss segment, of the steel truss of  FIG. 2B , according to one embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     An apparatus, system, method, and method of manufacture for a three-dimensional jacket-plate connector to connect at least two members that are wide-flanged steel I-beam sections, are described herein. The following detailed description is intended to provide example implementations to one of ordinary skill in the art, and is not intended to limit the invention to the explicit disclosure, as one of ordinary skill in the art will understand that variations can be substituted that are within the scope of the invention as described. 
     System Overviews ( FIGS. 1 and 2 ) 
       FIGS. 1A-E  are schematic diagrams illustrating steel frames, according to some embodiments. The steel frames are composed of steel I-beam sections that connect at a joint. The label numbers associated with the joints in  FIGS. 1A-E  correspond to figure numbers that further detail the joint. More particularly,  FIG. 1A  shows a steel frame with moment connections  3 ,  4 ,  5  and  6  further detailed in  FIGS. 3A-B ,  4 A-B,  5 A-B and  6 A-B;  FIG. 1B  shows an eccentrically braced frame (EBF) with moment connections  7 ,  9  and  10 , further detailed in  FIGS. 7A-D ,  9 A-D and  10 A-D, respectively; and  FIG. 1C  shows a specially concentrically braced frame (SCBF) with a moment connection  8  further detailed in  FIG. 8A-D . 
       FIGS. 2A-D  are schematic diagrams illustrating steel trusses, according to some embodiments. The label numbers associated with the joints in  FIGS. 2A-D  correspond to figure numbers that further detail the joint. Specifically,  FIG. 2A  illustrates a Vierendeel truss connection condition  15  further detailed in  FIGS. 15A-C ,  FIG. 2B  shows a steel bridge truss segment further detailed in  FIGS. 16A-B ,  FIG. 2C  shows an EBF and an inverted V SCBF with a moment connection  9  further detailed in  FIGS. 9A-D , and  FIG. 2D  shows a steel truss with a connection  8  further detailed in  FIGS. 8A-D . 
     Individual 3-D Connector and Accessory Details 
       FIGS. 3A-B  are schematic diagrams illustrating a moment connection  300  at a top floor, corner condition, of the steel frame of  FIG. 1A , according to some embodiments.  FIG. 3A  shows the moment connection  300  as assembled in the field, while  FIG. 3B  is an exploded view. The moment connection  300  is an (L)-shaped connection. The top floor corner  300  includes a 3-D connection between, for example, a post  310  and a beam  320  (also generically referred to as members herein). The 3-D connection includes 3-D jacket plates  301 ,  302 , which are mirror images to each other. 
     The post  310  and beam  320  are configured as I-beams or I-beam sections (i.e., two opposing flanges connected by a web). The members  310 ,  320  are composed of construction-grade steel, or any appropriate material. The sizes are variable. In some embodiments, the post  310  and beam  320  are different sizes because the post  310  typically supports a load of greater magnitude. 
     The 3-D jacket plates  301 ,  302  are composed of, for example, steel. The plates  301 ,  302  can be substantially identical and mirrored for attachment to opposite sides of the joint. The plates can be pre-fabricated off site to match sizes and strength requirements of the structure. Common sizes can be mass produced in a manufacturing facility. The 3-D jacket plates  301 ,  302  can be formed from c-channels having a web (or side) plate welded to two flange (or clamping) plates. Alternatively, the 3-D jacket plates  301 ,  302  can be formed from a side plate in the shape of a joint (i.e., (L)-shaped) and clamping plates welded around a perimeter of the side plate at, for example, a perpendicular angle. 
     In some embodiments, formation or manufacture of the 3-D jacket plates  301 ,  302  begins with a primary c-channel which can correspond to a primary member continued through joint. A connecting c-channel corresponding to a connecting member (i.e., the beam  320 ) can be welded to the primary c-channel. The primary member can be a load carrying member of a connection (i.e., the post  310 ), and the connecting member (i.e., the beam  320 ) can transfer its load to the primary member. The c-channels radiate away from the joint in the direction matching the members  310 ,  320 . A sidewall portion of the primary c-channel (i.e., portion of flange or clamping plate) can be notched out to weld a primary c-channel web to a connecting c-channel web. The notch accommodates flanges of the connecting member when installed. The connecting member transfers forces to the primary member through the pair of 3-D jacket plates  301 ,  302 . 
     Bolts can be used to connect the 3-D jacket plates  301 ,  302  to members. In one embodiment, a pre-drilled pattern is provided to allow faster installations. Configuration of c-channels of the 3-D jacket plates  301 ,  302  relative to connecting I-beam member  320  allows an installer to fit a hand with a fastening tool into a box gap afforded by opposing flanges of the I-beam and the webs of the c-channel and the I-beam. 
     One or more tension rods  303  installed across the depth (i.e., through-the-depth steel rods) of the post  310 , in some embodiments, provide additional strength to the primary c-channel of the 3-D jacket plates  301 ,  302 . Although the tension rods  303  are shown as connected to the post  310 , this is merely for the purpose of illustration. As installed, the tension rods  303  are connected to the outer portions of the 3-D jacket plates  301 ,  302  to reinforce against moment forces. More specifically, the vertical shear force is transferred from the beam  320  to the post  310  through a shear tag similar to those of  505  and  605 , the rotational moment force is completely transferred, from the beam  320  to the post  310 , through the 3-D jacket plates  301 ,  302 . The tension rods  303  help to transfer horizontal shear force associated with the moment force, through an inner flange, to the web of the post  310 . In other word, the tension rods  303  reinforce the connector plates  301 ,  302  from being pulled away from the outer flange. 
     Stiffener (or web stiffener) plates  304  in the post  310 , of other embodiments, provide additional strength to the continued primary I-beam  310 . One more stiffener plates  304  are dispersed as needed. The stiffener plates  304 , coupled with the tension rods  304 , help in transferring bending moment and shear force across the connection. 
       FIGS. 4A-B  are schematic diagrams illustrating a moment connection  400  at an intermediate floor, side condition, of the steel frame of  FIG. 1A , according to some embodiments. 
     In this embodiment, the jacket plates  401 ,  402  have a (T)-shape (rotated), and are substantially mirror in configuration. As an intermediate floor connection, a beam  420  that is supported by a post  410  which continues vertically to provide support for members at higher elevations, such as a top floor or a roof. 
     The jacket plates  401 ,  402  have a primary c-channel corresponding to the post  410  and a connecting c-channel corresponding to the beam  420 . One way to form the jacket plates  401 ,  402  is to notch out a flange (or clamping) plate of the primary c-channel to allow accommodation for the flanges of beam  420 . 
     Tension rods  403  and stiffener plates  404  are placed to counteract the moment force generated by member  420 . Both upper and lower reinforcement are used against both the clockwise and counter clockwise potential rotation of member  420 . A shear tag (similar to those of  505  and  605 , but not shown) can also be included. 
       FIGS. 5A-B  are schematic diagrams of a moment connection  500  at a top floor, interior bay condition, of the steel frame of  FIG. 1A , according to some embodiments. 
     In this embodiment, the jacket plates  501 ,  502  have a (T)-shape, and are substantially mirror in configuration. Relative to the moment connection  400  of  FIG. 4 , the moment connection  500  supports beams on either side of a post rather than at different vertical elevations. Further, tension rods  503  and stiffener plates  504  are dispersed only below the joint. A shear tag  505  is provided to transfer vertical shear forces from I-beam  530  to the post  510 . The rotational moment force is completely transferred, from the beams  520  and  530  to the post  510 , through the 3-D jacket plates  501 ,  502 . 
       FIGS. 6A-B  are schematic diagrams illustrating a moment connection  600  at an intermediate floor, interior bay condition, of the steel frame of  FIG. 1A , according to some embodiments. 
     In this embodiment, the jacket plates  601 ,  602  have a (+)-shape, and are substantially mirror in configuration. In this implementation, the moment connection  600  supports beams  620 ,  630  on either side of a post  610  and at different vertical elevations. Here, upper and lower reinforcements are in place. Specifically, tension rods  603 , stiffener plates  604  and a shear tag  605  are shown. 
     Additional variations are possible which do not have 90 degree angle joints and have more than two members. The angles can be 45, 30 or 60 degrees, or any angle needed for a structure. In  FIGS. 7-16 , numbering labels are consistent with the earlier figures in that connector plates label numbers start with the figure number and end with 01 and 02, tension rods end with 03, web stiffeners end with 04, and shear tags end with 05. 
     In particular,  FIGS. 7A-D  are schematic diagrams illustrating a moment connection  700  of an eccentrically braced frame (EBF), of the steel frame of  FIG. 1B , according to some embodiments. In this embodiment, the jacket plates  701 A,  702 A,  701 B and  702 B have a (y)-shape (rotated), and are substantially mirror in configuration. 
       FIGS. 8A-D  are schematic diagrams illustrating a moment connection  800  of a special concentrically braced frame (SCBF), of the steel frame of  FIG. 1C  of the steel truss of  FIG. 2D , according to some embodiments. In this embodiment, the jacket plates  801  and  802  have the shape of a combination of two rotated and mirrored (y)-shapes, and are substantially mirror in configuration. 
       FIGS. 9A-D  are schematic diagrams illustrating a moment connection  900  of an EBF and an inverted V SCBF, brace and beam to column connection, of the steel frame of  FIG. 1B  and the steel truss of  FIG. 2C , according to some embodiments. In this embodiment, the jacket plates  901  and  902  have the shape of a combination a rotated (T) and (y), and are substantially mirror in configuration. 
       FIGS. 10A-D  are schematic diagrams illustrating a moment connection  1000  of an EBF and an inverted V SCBF, brace and column connection at a foundation, of the steel frame of  FIG. 1B , according to one embodiment. In this embodiment, the jacket plates  1001  and  1002  have a tilted (V)-shape, and are substantially mirror in configuration. 
       FIGS. 11A-D  are schematic diagrams illustrating a moment connection  1100  of an SCBF, brace and beam to column connection at a floor, of the steel frame of  FIG. 1D , according to one embodiment. In this embodiment, the jacket plates  1101  and  1102  have the shape of a combination of a (K)-shape and a rotated (T)-shape, and are substantially mirror in configuration. 
       FIGS. 12A-F  are schematic diagrams illustrating a moment connection  1200  of an SCBF, brace and beam to column connection at a top floor, of the steel frame of  FIG. 1E , according to some embodiments. In this embodiment, the jacket plates  1201  and  1202  have the shape of a combination of a rotated (L)-shape and rotated (V)-shape, and are substantially mirror in configuration. 
       FIGS. 13A-B  are schematic diagrams illustrating a moment connection  1300  of an SCBF, brace and beam crossing connection, of the steel frame of  FIG. 1D , according to some embodiments. In this embodiment, the jacket plates  1301  and  1302  have a rotated back-to-back dual (K)-shape, and are substantially mirror in configuration. 
       FIGS. 14A-C  are schematic diagrams illustrating a moment connection  1400  of an SCBF, brace crossing connection without beam condition, of the steel frame of  FIG. 1E , according to some embodiments. In this embodiment, the jacket plates  1401  and  1402  have a (X)-shape, and are substantially mirror in configuration. 
       FIGS. 15A-C  are schematic diagrams illustrating a Vierendeel truss, connection condition, of the steel truss of  FIG. 2A , according to one embodiment. In this embodiment, the jacket plates  1501 A and  1502 A have a (T)-shape, and are substantially mirror in configuration; the jacket plates  1501 B and  1502 B have a inverted (T)-shape, and are substantially mirror in configuration. 
     Finally,  FIGS. 16A-B , are schematic diagrams illustrating a steel bridge truss segment, of the steel truss of  FIG. 2B , according to one embodiment. In this embodiment, the jacket plates  1651  has a inverted (T)-shape; the jacket plates  1652  and  1653  has the shape of a combination of a rotated (K)-shape and rotated (T)-shape; and the jacket plates  1654  has a (T)-shape.