Patent Publication Number: US-10760261-B2

Title: Beam-to-column connection systems and moment-resisting frames including the same

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application No. 62/265,362 filed on 9 Dec. 2015, the disclosure of which is incorporated herein, in its entirety, by this reference. 
    
    
     BACKGROUND 
     Typically, structural beam-to-column connections in moment-resisting frames can be very expensive to build, because they include multiple parts that must be fitted and then welded together. For example, the parts required for the moment-resisting frame may include a column, column continuity plates, column doubler plates, and a beam. The welding between the beam and the column is typically performed in the field and can be particularly expensive. Another connection type includes a flange-plate moment connection and addresses the expense of welding. Generally, however, when the frame experiences a seismic event, the connection between the beam and the column is such that the failure or yielding of the frame occurs at a location on the beam, which is near but not at the connection. 
     Accordingly, designers and manufacturers of moment-resisting frame continue to seek improvements thereto. 
     SUMMARY 
     Embodiments disclosed herein relate to a seismic fuse plate for a moment-resisting frame as well as to a connection system and a moment-resisting frame that include such seismic fuse plate. Specifically, the seismic fuse plate may be configured and positioned such that movement or tilting of the moment-resisting frame exerts shear forces on one or more portions of the seismic fuse plate. For example, as the moment-resisting frame experiences a seismic event (e.g., an event that may exert forces onto the moment-resisting frame, which may tilt or reconfigure the moment-resisting frame from a generally rectangular configuration to a parallelogram configuration), the seismic fuse plate may be subjected to shear force that may preferentially fail the seismic fuse plate instead of the beam and/or column connected by the connection system that includes the seismic fuse plate. 
     An embodiment includes beam-to-column connection system that includes a first pair of splice plates configured to be secured to the column and to be spaced from each other along the column at a first distance, and a second pair of splice plates configured to be secured to the column and opposite to the first pair of splice plates, and to be spaced from each other along the column at the first distance. The beam-to-column connection system also includes a first seismic fuse plate that includes a beam-connection portion configured to connect to a first flange of the beam, a first splice-connection portion longitudinally extending along at least a portion of the beam-connection portion and being configured to connect to and between the first pair of splice plates, and a second splice-connection portion longitudinally extending along at least a portion of the beam-connection portion and being configured to connect to and between the second pair of splice plates at a second location, the distance between the first and second location being greater than the width of the beam. The first seismic fuse plate also includes a first shear portion extending between the first splice-connection portion and the beam-connection portion. 
     Another embodiment includes a moment-resisting frame that includes a column having a column width, a beam having a beam width, and a beam-to-column connection system connecting the beam to the column. The beam-to-column connection system includes a first pair of splice plates connected to a first side of the column and spaced from each other along the first side of the column at a first distance, a second pair of splice plates connected to a second side of the column and spaced from each other along the first side of the column at the first distance, and a first seismic fuse plate secured between the first pair of splice plates and between the second pair of splice plates. The first seismic fuse plate includes a beam-connection portion connected to the a first flange of the beam, and a first shear portion located between the beam-connection portion and the first pair of splice plates. 
     Features from any of the disclosed embodiments may be used in combination with one another, without limitation. In addition, other features and advantages of the present disclosure will become apparent to those of ordinary skill in the art through consideration of the following detailed description and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate several embodiments, wherein identical reference numerals refer to identical or similar elements or features in different views or embodiments shown in the drawings. 
         FIG. 1  is an isometric partial view of a moment-resisting frame, according to an embodiment; 
         FIG. 2A  is a top partial view of the moment-resisting frame of  FIG. 1 ; 
         FIG. 2B  is a front partial view of the moment-resisting frame of  FIG. 1 ; 
         FIG. 2C  is an end partial view of the moment-resisting frame of  FIG. 1 ; 
         FIG. 3A  is a schematic front view of the moment-resisting frame of  FIG. 1  under an example load from a seismic event that delivers energy to the moment-resisting frame and causes minimal deformation of a seismic fuse plate that is included in the moment-resisting frame; 
         FIG. 3B  is a top view of the seismic fuse plate exposed to the loads shown in  FIG. 3A ; 
         FIG. 4A  is a schematic front view of the moment-resisting frame of  FIG. 1  under another example load from a seismic event that delivers energy to the moment-resisting frame and causes plastic deformation or failure of a seismic fuse plate that is included in the moment-resisting frame; 
         FIG. 4B  is a top view of the seismic fuse plate exposed to the loads shown in  FIG. 4A ; 
         FIG. 5  is a top view of a seismic fuse plate, according to an embodiment; 
         FIG. 6  is a top view of a seismic fuse plate, according to another embodiment; 
         FIG. 7A  is a top view of a seismic fuse plate, according to yet another embodiment; 
         FIG. 7B  is a cross-sectional view of the seismic fuse plate of  FIG. 7A ; and 
         FIG. 8  is a top view of a seismic fuse plate, according to another embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments disclosed herein relate to a seismic fuse plate for a moment-resisting frame as well as to a connection system and a moment-resisting frame that includes such seismic fuse plate. Specifically, the seismic fuse plate may be configured and positioned such that movement or tilting of the moment-resisting frame exerts shear forces on one or more portions of the seismic fuse plate. For example, as the moment-resisting frame experiences a seismic event (e.g., an event that may exert forces onto the moment-resisting frame, which may tilt or reconfigure the moment-resisting frame from a generally rectangular configuration to a parallelogram configuration), the seismic fuse plate may be subjected to shear force that may preferentially fail the seismic fuse plate instead of the beam and/or column connected by the connection system that includes the seismic fuse plate. 
     In some embodiments, the connection system may be configured to prevent or reduce the likelihood of buckling at one or more portions of the beam and/or column connected by the connection system. For example, failure resulting from shear forces experienced by the seismic fuse plate at the connection system may accommodate or allow greater relative rotation or pivoting between the beam and column connected by the connection system (e.g., as compared with a conventional connection system) without failure of the beam and/or column. Facilitating increased tilting between the beam and column connected by the connection system (compared with a conventional connection) without buckling the beam and/or column may prevent failure or deformation of the beam (e.g., which may be more costly to repair than repairing or replacing the connection system). For example, instead of buckling or otherwise plastically deforming the beam, during a seismic event, the seismic fuse plate may experience elastic and/or plastic deformation resulting from the shear forces experienced thereby, while the deformations experienced by the beam and the column may remain in the elastic region, thereby preventing damage to the beam and column. Moreover, one or more portions of the connection system (e.g., the seismic fuse plate) may be replaced. As noted above, replacing a failed or plastically deformed seismic fuse plate may be easier and/or less expensive than replacing a failed or plastically deformed beam or column. 
     Generally, the seismic fuse plate may have any number of suitable configurations, such that the seismic fuse plate may be subjected to and/or fail due to shear forces (e.g., in a seismic event) of a selected magnitude. For example, the seismic fuse plate may include at least one shear portion that may selectively fail during a seismic event, may have any suitable shape and/or cross-section that may have a suitable shear strength. Hence, for example, by selecting a suitable shear strength for the shear portion(s) of the seismic fuse plate, the moment-resisting frame may be configured such as to fail due to the shear forces applied at the shear portion of the seismic fuse plate, while the column and beam connected by the connection system may remain undamaged. 
       FIG. 1  is an isometric partial view of a moment-resisting frame  100  according to an embodiment. Specifically, the moment-resisting frame  100  illustrated in  FIG. 1  includes a beam  200  connected to a column  300  by a beam-to-column connection system  400 . As described above, the beam-to-column connection system  400  may include one or more seismic fuse plates, such as first and second seismic fuse plates  410   a ,  410   b , which may selectively fail or elastically deform during a seismic event, thereby absorbing energy (e.g., in the a manner that may protect or prevent plastic deformation of the beam  200  and/or of the column  300 ). 
     Generally, the beam-to-column connection system  400  may include any number of suitable connections that may be configured to connect the first seismic fuse plate  410   a  and/or second seismic fuse plate  410   b  to the column  300 . In the illustrated embodiment, the first seismic fuse plate  410   a  may be connected to the column  300  by opposing first and second pairs of splice plates  420   a ,  420   a ′. Similarly, the seismic fuse plate  410   b  may be connected to the column  300  by opposing third pair of splice plates  420   b  and fourth pairs of splice plates  420   b ′. In the illustrated embodiment, multiple respective fasteners (e.g., bolts  430 ) may connect the first and second pairs of splice plates  420   a ,  420   a ′ to the first seismic fuse plate  410   a . Likewise, in the illustrated embodiment, the first seismic fuse plate  410   a  may be connected to the beam  200  with multiple fasteners (e.g., bolts  430 ). Similarly, the seismic fuse plate  410   b  may be connected to the third pair of splice plates  420   b  and to the fourth splice plate (not visible in the  FIG. 1 ) by one or more fasteners, such as by bolts  430 . 
     The first and second pairs of splice plates  420   a  and  420   a ′ may extend outward from the column  300  (e.g., generally in the direction of the beam  200 ). In the illustrated embodiment, the beam-to-column connection system  400  may include doubler plates  440   a ,  440   b  that may be secured to the column  300 . For example, the doubler plates  440   a ,  440   b  may be welded or otherwise secured to the column  300  with any number of suitable fastening mechanisms (e.g., fasteners, such as bolts, rivets, etc., welds, etc.). In an embodiment, the first pair of splice plates  420   a  may be secured to the doubler plate  440   a  (e.g., the first pair of splice plates  420   a  may be fastened to the  440   a  with one or more fasteners, such as with bolts  430 ). Similarly, the second first pair of splice plates  420   a ′ may be connected to the  440   b  (e.g., the second first pair of splice plates  420   a ′ may be fastened to the  440   b  with one or more fasteners, such as with one or more bolts). 
     Also, the third pair of splice plates  420   b  may be secured to the doubler plate  440   a  with one or more fasteners (e.g., with one or more bolts  430 ). Hence, for example, the first pair of splice plates  420   a  and the third pair of splice plates  420   b  may be positioned on the same side of the column  300  and may be spaced apart from each other. Moreover, the second pair of splice plates  420   a ′ and the fourth pair of splice plates  420   b ′ may be located on the same side of the column  300  (e.g., opposite to the respective first pair of splice plates  420   a  and the third pair of splice plates  420   b ). Similarly, the second pair of splice plates  420   a ′ and the fourth splice plates may be spaced apart along the column  300  (e.g., the second first pair of splice plates  420   a ′ may have generally the same longitudinal position along the column  300  as the first pair of splice plates  420   a , and the fourth pair of splice plates  420   b ′ may have generally the same longitudinal position along the column  300  as the  420   b ). 
     In the illustrated embodiment, the first pair of splice plates  420   a  is positioned above the third pair of splice plates  420   b  along the column  300 . For example, the first pair of splice plates  420   a  may secure a portion of the first seismic fuse plate  410   a , and the third pair of splice plates  420   b  may secure a portion of the seismic fuse plate  410   b . The first seismic fuse plate  410   a  may be spaced apart from (e.g., positioned above) the first seismic fuse plate  410   b , such that the beam  200  may be positioned between the first and second seismic fuse plates  410   a ,  410   b  and secured thereto. For example, as described above the first and second seismic fuse plates  410   a ,  410   b  may secure the beam  200  to the column, such that the beam  200  is secured between the first and second seismic fuse plates  410   a ,  410   b.    
     The beam  200  may be an I-beam that has a top flange  210 , a bottom flange  220 , and a web  230  extending therebetween. It should be appreciated that the beam  200  may have any number of suitable shapes (e.g., round tube, square tube, etc.). In the embodiment shown in  FIG. 1 , the first seismic fuse plate  410   a  may be secured to the top flange  210 , and the seismic fuse plate  410   b  may be secured to the bottom flange  220  of the beam  200  (e.g., the beam  200  may be oriented relative to the column  300 , such that the top flange  210  and the bottom flange  220  are spaced from each other along a direction that is generally parallel to the longitudinal direction of the column  300 ). Hence, for example, the first seismic fuse plate  410   a  and seismic fuse plate  410   b  may position and orient the beam  200  at a suitable orientation and position relative to the column  300 . 
     Generally, the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b  may extend outward from the column  300  in the same direction as the beam  200 . In the illustrated embodiment, the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b  orient the beam  200  substantially perpendicularly relative to the column  300  (e.g., the column  300  may be oriented along a substantially vertical axis  10 , the beam  200  may be oriented generally along a substantially horizontal axis  20 , and the vertical and horizontal axes  10 ,  20  may be substantially perpendicular to each other). In additional or alternative embodiments, the beam  200  may be oriented at any suitable angle relative to the column  300  (e.g., at obtuse or acute angles relative to the column  300 ). For example, the first, second, and third pairs of splice plates  420   a ,  420   a ′,  420   b , and the fourth splice plates may be secured to the corresponding doubler plates  440   a ,  440   b , such as to form a suitable angle relative to the column  300  and to orient the beam  200  at the suitable angle relative to the column  300 . 
     The first and second pairs of splice plates  420   a ,  420   a ′, and the third and fourth pairs of splice plates  420   b ,  420   b ′ may be spaced apart by a suitable distance, such as to accommodate the beam  200  of any selected thickness (e.g., thickness that may be defined by distance between the outer surfaces of the top flange  210  and bottom flange  220 ). That is, the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b  may be positioned at suitable distance along the column  300  to secure the beam  200  of any selected thickness. Moreover, the beam-to-column connection system  400  may be positioned at any suitable height along the column  300 , such that the beam  200  is positioned at a corresponding suitable height. 
     In the illustrated embodiment, the column  300  is an I-beam that includes flanges  310 ,  320  and a web  330  therebetween. For example, the column  300  may be axially oriented and/or centered about the axis  10 , such that axis  10  is positioned midway between the flanges  310  and  320 . In an embodiment, the flanges  310 ,  320  may be generally perpendicular to the axis  20  that may be generally perpendicular to the axis  10  (e.g., the longitudinal direction of the beam  200  may be generally perpendicular to the outer surfaces of the flanges  310  and  320 ). It should be appreciated, however, that the beam  200  may have any number of suitable orientations relative to the shape of the column  300  (e.g., relative to the flanges  310  and/or  320 ). Moreover, the column  300  may have any number of suitable cross-sectional shapes (e.g., tubular rectangle, tubular round, etc.). 
     In the illustrated example, the first seismic fuse plate  410   a  and seismic fuse plate  410   b  are connected to the column  300  by the first and second pairs of splice plates  420   a ,  420   a ′ and the third pair of splice plates  420   b  and fourth splice plates (respectively) that are connected to the doubler plates  440   a ,  440   b . In particular, in the illustrated embodiment, the  440   a  and  440   b  may be connected to the column  300  with one or more welds (e.g., fillet welds may connect the  440   a  and  440   b  to the flanges  310  and  320 ). Generally, however, the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b  may be connected to the column  300  with any number of suitable connect systems and mechanism. Examples of suitable connection systems and mechanisms are more fully described in PCT International Application No. PCT/US2015/047006 filed on 26 Aug. 2015, the disclosure of which is incorporated herein in its entirety by this reference. 
       FIGS. 2A-2C  are partial top, front, and end views, respectively, of the moment-resisting frame  100 . Conventionally, the beam secured to the column may have a weakened portioned (e.g., near the connection location) that may fail or plastically deform during a seismic event. For example, conventional moment-resisting frames or frame connections may be configured in a manner that allows one or more portions of the beam to plastically deform, thereby absorbing some of the energy that the seismic event delivered to the moment-resisting frame (e.g., to avoid critical damage to or failure of the frame). 
     In particular, for example, the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b  may fail or plastically deform, to absorb energy from the seismic event, due to shear forces experience thereby (e.g., forces in a direction generally parallel to the axis  20 ). As described above, the seismic fuse plate(s), such as the first and second seismic fuse plates  410   a ,  410   b  may absorb some of the energy that a seismic event may deliver to the moment-resisting frame  100 . Specifically, for example, dissipating the energy from the seismic event by allowing the seismic fuse plate(s) to deform and/or at least partially shear may prevent or avoid deformations to the beam  200  and/or to the column  300  (e.g., that may otherwise result from the seismic event). 
     In an embodiment, the beam  200  may be spaced from the column  300  by a space  30 . Hence, for example, the first seismic fuse plate  410   a  and the second seismic fuse plate may experience shear forces as the beam  200  moves toward and/or away from the column  300  during a seismic event. As described below in more detail, positioning the beam  200  spaced from the column  300  along the axis  20  (e.g., by a suitable distance) and secured to the column  300  by the beam-to-column connection system  400  may allow the beam  200  to move in a direction that is generally parallel to the axis  20  as the frame tilts. In some embodiments, the axis  20  together with the beam  200  may change orientation relative to the column  300  and relative to the axis  10 , as the moment-resisting frame  100  tilts during a seismic event. Furthermore, the beam  200  may apply or produce shear force on the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b , as the frame tilts and the beam  200  is forced to change orientation relative to the column  300  (e.g., from a generally perpendicular orientation to forming an acute and/or obtuse angle relative thereto). 
     In some embodiments, the first seismic fuse plate  410   a  and the second seismic fuse plate  410   b  may have similar or the same configurations. Hence, for the sake of simplicity, the following describes to the first seismic fuse plate  410   a , but would be similarly applicable to the second seismic fuse plate  410   b . For example, the seismic fuse plate  410   a  may have at least one portion that is wider than the width of the beam  200  (e.g., a portion of the seismic fuse plate  410   a  that is near the column  300  may be wider than the width of the beam  200 ). Moreover, in some embodiments, the first pair of splice plates  420   a  and the second pair of splice plates  420   a ′ may be secured to the seismic fuse plate  410   a  at the portion that is wider than the beam  200  (e.g., the first pair of splice plates  420   a  and the second first pair of splice plates  420   a ′ may be positioned about the beam  200  such as to define a distance therebetween that is greater than the width of the beam  200 . 
     In an embodiment, at least one portion of the seismic fuse plate  410   a  may be positioned between the beam  200  one an outer periphery of the beam  200  (e.g., without contacting any other portion of the beam  200 , column  300 , other portions of the beam-to-column connection system  400 , or combination thereof). The seismic fuse plate  410   a  may include first and second shear portions  411   a ,  411   a ′. Specifically, for example, the first shear portion  411   a  may extend between a beam-connection portion (e.g., portion of the seismic fuse plate  410   a  that may be connected to the beam  200 ) and a splice-connection portion (e.g., portion of the seismic fuse plate  410   a  that is secured between the first pair of splice plates  420   a ). Similarly, the second shear portion  411   a ′ may extend between the beam-connection portion (e.g., portion of the seismic fuse plate  410   a  that may be connected to the beam  200 ) and another splice-connection portion (e.g., portion of the seismic fuse plate  410   a  that is secured between the second pair of splice plates  420   a ′). Hence, under some operating conditions, the first and second shear portions  411   a  and/or  411   a ′ may fail, as the beam  200  is forced away from and/or toward the column  300 . 
     In some embodiments, the beam-to-column connection system  400  may include a blocker plate  450  that may prevent or limit movement of the beam  200  toward the column  300 . For example, as shown in  FIGS. 2A-2C , the blocker plate  450  may be secured to the beam  200  (e.g., to the web of the beam  200 ) and may abut the column  300  (e.g., may abut the flange of the column  300 ). In the illustrated example, the blocker plate  450  is fastened to the beam  200  with fasteners. It should be appreciated, however, that the blocker plate  450  may be attached to the beam  200  with any number of suitable connections (e.g., weld, rivets, etc.). 
     Moreover, the blocker plate  450   a  may be detached from the beam  200 . For example, the blocker plate  450   a  may be attached to the beam  200  after the beam  200  is positioned at the suitable location relative to the column  300  (e.g., without the blocker plate  450   a , the beam  200  may be positioned between two opposing columns, such that the beam  200  is suitably shorter than the distance between the two opposing columns, to facilitate installation of the beam  200 ). Furthermore, the blocker plate  450  may prevent or limit the beam  200  from moving toward the column  300  but may not stop or limit movement of the beam  200  away from the column  300 . 
     In other words, the blocker plate  450  may provide additional restraint (e.g., in addition to the seismic fuse plate  410   a ) for the beam  200  to move toward the column  300 . It should be appreciated, however, that beam  200  may be restrained from moving toward the column  300  with any number additional or alternative elements (e.g., a blocker plate or block may be secured to the column  300  and may abut the end of the beam  200 ). Moreover, the beam  200  may be sized such that the end of the beam  200  abuts the column  300 . 
     In an embodiment, in a seismic event that applies lateral load onto the moment-resisting frame  100  (e.g., in directions along the axis  20 ), the seismic fuse plate  410   a  may experience a greater load when the beam  200  experiences forces in the direction away from the column  300  than when the beam  200  experiences forced in the direction toward the column  300 . As such, under some operating conditions, the seismic fuse plate  410   a  may be more prone to failure when the beam  200  is forced away from the column  300 . In other words, the beam-to-column connection system  400  may be configured such that the seismic fuse plate  410   a  may selectively plastically deform and/or fail in a single direction (e.g., due to shear forces at the first and second shear portions  411   a ,  411   a ′). As described above, in some conventional frames, the beam may be selectively weakened near the connection to the column; such weakened portion may fail in response to repeated compressive and tensile loads thereof (e.g., due to buckling). 
       FIG. 3A  is a schematic front view of the moment-resisting frame  100  under an example load from a seismic event.  FIG. 3B  shows the forces experienced by the seismic fuse plate  410   a  of the beam-to-column connection system  400 , according to the loading shown in  FIG. 3A . The moment-resisting frame  100  may experience a seismic event that may produce lateral forces that generally push the moment-resisting frame  100  laterally to the left (as shown in  FIG. 3A ) and/or in the opposite direction, to the right. 
     The moment-resisting frame  100  may include a beam  200  connected to and between opposing columns  300  and  300   a , thereby forming a substantially rigid structure that may resist lateral forces (e.g., the moment-resisting frame  100  may be included in a structure, such as a building, and may provide suitable resistance to lateral movements, which may prevent collapse of the building under certain conditions). As described above, the beam  200  may be connected to the column  300  by the beam-to-column connection system  400 . Furthermore, the beam  200  may be connected to the column  300   a  by a beam-to-column connection system  400   a  that may be similar to or the same as the beam-to-column connection system  400  (e.g., as described above). 
     In the illustrated example, the beam-to-column connection system  400  includes the seismic fuse plate  410   a  and seismic fuse plate  410   b  that experience shear load (as shown in  FIG. 3B  in connection with the  410   a ). Conversely, the beam-to-column connection system  400   a  may include seismic fuse plate  410   c  and seismic fuse plate  410   d  (that may be similar to or the same as the respective seismic fuse plate  410   a  and seismic fuse plate  410   b ), which may experience compressive load. Moreover, as mentioned above, the beam-to-column connection system  400  and/or the beam-to-column connection system  400   a  may include one or more blocker plates that may provide additional compressive strength to the beam-to-column connection system  400  (e.g., the seismic fuse plate  410   a  and seismic fuse plate  410   b  may experience greater shear loads than the shear loads experienced by the seismic fuse plate  410   c  and seismic fuse plate  410   d ). 
     As described above, the seismic fuse plate  410   a  may include the shear portions  411   a  and  411   a ′ that may be positioned and configured such as not to contact any other portion of the beam  200 , column  300 , beam-to-column connection system  400 , or combinations thereof. For example, the seismic fuse plate  410   a  may include a beam-connection portion  412  that may generally extend along the middle of the seismic fuse plate  410   a  and may be connected to the beam. The seismic fuse plate  410   a  also may include a first splice-connection portion  413   a  and a second splice-connection portion  413   a ′. In an embodiment, the first splice-connection portion  413   a  may be secured to the first pair of splice plates and the second splice-connection portion  413   a ′ may be secured to the second pair of splice plates. For ease of identification,  FIG. 3B  illustrates the first and second shear portions  411   a  and  411   a ′ without any shading, the beam-connection portion  412   a  is shown with a first cross-hatch, and the first and second splice-connection portion  413   a ,  413   a ′ are shown with a second cross-hatch (the cross-hatches only demarcate the respective portions and are not used to indicate a cross-section at the cross-hatched locations). 
     In an embodiment, the first and second shear portions  411   a  and  411   a ′ may be positioned between the portions of the seismic fuse plate  410   a , which may be secured to the beam or to the column. For example, the first shear portion  411   a  may be positioned between the beam-connection portion  412   a  (secured to the beam) and the first splice-connection portion  413   a  (secured to the first pair of splice plates). Likewise, the second shear portion  411   a ′ may be positioned on an opposite side of the seismic fuse plate  410   a  and between the beam-connection portion  412   a  (secured to the beam) and the second splice-connection portion  413   a ′ (secured to the second pair of splice plates). 
     Hence, for example, as the beam  200  and the column  300  experience forces in the opposite directions (as shown in  FIGS. 3A-3B ), the beam-connection portion  412   a  on the one hand and the first splice-connection portion  413   a  and second splice-connection portion  413   a ′ on the other hand may experience the same forces as the beam  200  and the column  300 , respectively (translated thereto through the splice plates and the beam connection). Moreover, as the first shear portion  411   a  is positioned between the beam-connection portion  412  and the  413   a , the first shear portion  411   a  may experience shear forces. Similarly, as the second shear portion  411   a ′ is positioned between the beam-connection portion  412  and the  413   a , the second shear portion  411   a ′ may experience shear forces (e.g., which may be similar to or the same as the shear forces experienced at the first shear portion  411   a ). 
       FIG. 4A  is a schematic illustration that shows the moment-resisting frame  100  after the seismic fuse plate  410   a  and the seismic fuse plate  410   b  deform (e.g., plastically or elastically deform) to facilitate lateral tilting of the moment-resisting frame  100 . It should be appreciated that the moment-resisting frame  100  is not shown to scale in  FIG. 4A .  FIG. 4B  the deformation of the seismic fuse plate  410   a  resulting from the tilt of the moment-resisting frame  100  shown in  FIG. 4A . In particular, as shown in  FIG. 4B , the first and second shear portions  411   a  and  411   a ′ may be deformed (plastically or elastically) due to the shear stress experienced thereat. 
     Generally, the amount of deformation and/or the forces required to produce the deformation (e.g., such as to plastically deform or fail the first and second shear portions  411   a  and/or  411   a ′ of the seismic fuse plate  410   a  and/or corresponding portions of the seismic fuse plate  410   b ) may vary from one embodiment to the next and may depend on the shape and size of the first and second shear portions  411   a ,  411   a ′, modulus of elasticity of the material of the seismic fuse plate  410  and/or material of the first and second shear portions  411   a ,  411   a ′, etc. 
     As described above, in some embodiment, the moment-resisting frame may have two or more beam-to-column connection systems that include at least one seismic fuse plate (e.g., two opposing beam-to-column connection systems). Additionally or alternatively, moment-resisting frames may include a single beam-to-column connection system with at least one seismic fuse plate. For example, a moment-resisting frame may include two opposing columns and a beam connected thereto; a beam-to-column connection system (e.g., as described above) may connect the beam to a first column, and another connection (e.g., another rigid connection, such as a welded connection) may connect the beam to a second column. 
     The seismic fuse plate  410   a  may have a plate-like configuration of a selected thickness. For example, the thickness of the seismic fuse plate  410   a  may be selected such that the first and second shear portions  411   a  and  411   a ′ have a suitable or selected failure point or force at which the first and second shear portions  411   a  and  411   a ′ plastically deform.  FIG. 5  is a top view of the seismic fuse plate  410   a  according to an embodiment. As shown in  FIG. 5  the seismic fuse plate  410   a  may have openings  414   a  extending through the thickness of the seismic fuse plate  410   a . In particular, for example, the openings  414   a  may weaken the first and second shear portions  411   a  and  411   a ′, such that the first and second shear portions  411   a  and  411   a ′ have suitable strength (e.g., such that the first and second shear portions  411   a  and  411   a ′ may deform to absorb energy of a seismic event and prevent deformation or damage to the beam and/or column connected thereby). In some embodiments, the shear portions may have other suitable shapes and sizes, as described below. 
     Also, as described above, the seismic fuse plate  410   a  may be fastened to the beam and to the splice plates. Hence, for example, the seismic fuse plate  410   a  may include fastener holes  415   a  at suitable locations for fastening the seismic fuse plate  410   a . Generally, however, the seismic fuse plate  410   a  may be fastened to the beam and to the splice plates with any number of suitable connections (e.g., weld, rivets, etc.). In some embodiments, the seismic fuse plate may have no holes or openings for fasteners. 
     It should be appreciated, however, that the shear portions of the seismic fuse plate may have any number of suitable configurations.  FIG. 6  is a top view of a seismic fuse plate  410   b  according to an embodiment. Except as otherwise described herein, the seismic fuse plate  410   b  may be similar to or the same seismic fuse plate  410   a  ( FIG. 5 ). For example, the seismic fuse plate  410   b  may include first and second shear portions  411   b  and  411   b ′ that may be defined by one or more cutouts extending from the edges of the seismic fuse plate  410   b  (e.g., by the cutouts  416   b ,  417   b  and cutouts  416   b ′,  417   b ′, respectively). 
     Moreover, in some embodiments, the shear portions may have a smaller thickness than other portions of the seismic fuse plate.  FIG. 7A  is a top view of a seismic fuse plate  410   c  according to an embodiment.  FIG. 7B  is a cross-sectional view of the seismic fuse plate  410   c , as indicated in  FIG. 7A . Except as otherwise described herein, the seismic fuse plate  410   c  may be similar to or the same any of the seismic fuse plates  410   a ,  410   b  ( FIGS. 5-6 ). For example, the seismic fuse plate  410   c  may include first and second shear portions  411   c ,  411   c ′ that may have one or more portions with smaller thicknesses than beam-connection portion  412   c  and/or first and second splice-connection portions  413   c ,  413   c′.    
     Furthermore, the seismic fuse plate may have any number of suitable configurations. In an embodiment, where the shear portions  411   c ,  411   c ′ of the seismic fuse plate may have selected strength, such as to produce a controlled plastic deformation and/or failure thereat. For example, the shear portions  411   c ,  411   c ′ may have a suitable or selected thickness, such that the shear portions  411   c ,  411   c ′ may deform or fail in response to selected shear forces applied thereto. 
       FIG. 8  is a top view of a seismic fuse plate  100   d , according to an embodiment. Except as otherwise described herein, the seismic fuse plate  410   d  may be similar to or the same any of the seismic fuse plates  410   a ,  410   b ,  410   c  ( FIGS. 5-7B ). For example, the seismic fuse plate  100   d  may have first and second shear portions  411   d ,  411   d ′, a beam-connection portion  412   d , and first and second splice-connection portions  412   d ,  412   d ′, which may be similar to the respective first and second shear portions  411   a ,  411   a ′, a beam connection portion  412   a , and first and second splice-connection portions  412   a ,  412   a ′ of the seismic fuse plate  100   d  ( FIG. 3B ). In the illustrated example, the first and second shear portions  411   d ,  411   d ′, the beam-connection portion  412   d , and first and second splice-connection portions  412   d ,  412   d ′ may have generally the same lengths (e.g., may extend between opposing edges  416   d ,  416   d ′ of the seismic fuse plate  410   d ). Moreover, it should be appreciated that the first and second shear portions  411   d ,  411   d ′, the beam-connection portion  412   d , and first and second splice-connection portions  412   d ,  412   d ′ may have any suitable widths (e.g., dimensions or sized that are generally perpendicular to the respective lengths). For example, the width of the beam-connection portion  413   d  may be generally the same as the width of one or more flanges of a beam. Moreover, the first and second shear portions  411   d ,  411   d ′, the beam-connection portion  412   d , and first and second splice-connection portions  412   d ,  412   d ′ may have substantially the same widths as one another or different widths. 
     In the illustrated embodiments in  FIGS. 2A-8 , the first and second seismic fuse plates (e.g., the first and second seismic plates  410   a ,  410   b  shown in  FIGS. 2A-2B ) include openings or cutouts therein. However, in other embodiments, one or both of the first or second seismic fuse plates of any of the moment-resistant frames and beam-to-column connection systems may lack the openings or the cutouts and may be generally imperforate. 
     While various aspects and embodiments have been disclosed herein, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting.