Abstract
A moment frame wall assembly includes a box wall frame having first and second columns spaced apart from one another and header and sill beams extending between the first and second columns. The beams are joined to the respective columns by respective beam-to-column joints. Each of the beam-to-column joints includes a yielding member that fails prior to failure of the respective beam and column joined by the respective beam-to-column joint due to external lateral forces applied to the moment frame wall assembly. The assembly includes a shear panel made of sheet metal. The shear panel has an upper edge margin attached to the header beam, a lower edge margin attached to the sill beam, a first side edge margin attached to the first column, and a second side edge margin attached to the second column. The shear panel resists the external lateral forces applied to the moment frame wall assembly.
Claims
1. A moment frame wall assembly comprising: a box wall frame including: first and second columns spaced apart from one another; a header beam extending between the first and second columns, the header beam being joined to the first column by a beam-to-column joint and being joined to the second column by another beam-to-column joint; and a sill beam extending between the first and second columns, the sill beam being joined to the first column by another beam-to-column joint and being joined to the second column by another beam-to-column joint; each of the beam-to-column joints including a yielding member configured to fail prior to failure of the respective beam and column joined by the respective beam-to-column joint due to external lateral forces applied to the moment frame wall assembly; and a shear panel made of sheet metal, the shear panel having an upper edge margin attached to the header beam, a lower edge margin attached to the sill beam, a first side edge margin attached to the first column, and a second side edge margin attached to the second column, the shear panel being configured to resist the external lateral forces applied to the moment frame wall assembly.
2. The moment frame wall assembly of claim 1, wherein the shear panel is configured to yield with the yielding members of the beam-to-column joints so that the shear panel and the yielding members of the beam-to-column joints work simultaneously to resist the external lateral forces applied to the moment frame wall assembly.
3. The moment frame wall assembly of claim 2, wherein each yielding member of the beam-to-column joints comprises a sheet metal panel.
4. The moment frame wall assembly of claim 3, wherein the sheet metal panel of the shear panel has a thickness less than or equal to a thickness of the sheet metal panel of the yielding members.
5. The moment frame wall assembly of claim 4, wherein the thickness of the sheet metal panel of the shear panel is 22 gauge.
6. The moment frame wall assembly of claim 1 wherein the shear panel includes opposite major surfaces and edges extending between the opposite major surfaces, the major surfaces of the shear panel extending between the header beam and the sill beam, and between the first and second columns.
7. The moment frame wall assembly of claim 1, wherein the shear panel is configured to yield with at least some of the yielding members of the beam-to-column joints.
8. The moment frame wall assembly of claim 1, further comprising: a first elongate member extending along the header beam and forcing the upper edge margin of the shear panel against the header beam; a second elongate member extending along the sill beam and forcing the lower edge margin of the shear panel against the sill beam; a third elongate member extending along the first column and forcing the first side edge margin of the shear panel against the first column; and a fourth elongate member extending along the second column and forcing the second side edge margin of the shear panel against the second column.
9. The moment frame wall assembly of claim 8, wherein: the shear panel includes a shear wall, a top wall, a bottom wall, a first side wall, and a second side wall; the shear wall of the shear panel overlapping and engaging a generally vertical face of the first elongate member, a generally vertical face of the second elongate member, a first generally vertical face of the third elongate member, and a first generally vertical face of the fourth elongate member; the top wall of the shear panel overlaps and engages a generally horizontal face of the first elongate member; the bottom wall of the shear panel overlaps and engages a generally horizontal face of the second elongate member; the first side wall of the shear panel overlaps and engages a second generally vertical face of the third elongate member; and the second side wall of the shear panel overlaps and engages a second generally vertical face of the fourth elongate member.
10. The moment frame wall assembly of claim 1, further comprising: a first series of fasteners attaching the upper edge margin of the shear panel to the header beam; a second series of fasteners attaching the lower edge margin of the shear panel to the sill beam; a third series of fasteners attaching the first side edge margin of the shear panel to the first column; and a fourth series of fasteners attaching the second side edge margin of the shear panel to the second column.
11. The moment frame wall assembly of claim 10, wherein: the first series of fasteners is spaced apart from a first interior corner formed by the first column and the header beam and is spaced apart from a second interior corner formed by the second column and the header beam; the second series of fasteners is spaced apart from a third interior corner formed by the first column and the sill beam and is spaced apart from a fourth interior corner formed by the second column and the sill beam; the third series of fasteners is spaced apart from the first interior corner and is spaced apart from the third interior corner; and the fourth series of fasteners is spaced apart from the second interior corner and is spaced apart from the fourth interior corner.
12. The moment frame wall assembly of claim 11, wherein the header beam includes a stiffener and the sill beam includes a stiffener, the first series of fasteners extending through the stiffener of the header beam, and the second series of fasteners extending through the stiffener of the sill beam.
13. The moment frame wall assembly of claim 1, wherein the first column includes a first face facing in a direction that is parallel to a length of the box wall frame, the second column includes a second face facing in a direction that is parallel to the length of the box wall frame, the header beam includes a header face facing in a direction that is parallel to a height of the box wall frame, and the sill beam includes a sill face facing in a direction that is parallel to the height of the box wall frame; and wherein the shear panel overlaps and engages the first face of the first column, the second face of the second column, the header face of the header beam, and the sill face of the sill beam.
14. The moment frame wall assembly of claim 13, wherein the first column includes a first stiffener forming the first face, the second column includes a second stiffener forming the second face, the header beam includes a third stiffener forming the header face, and the sill beam includes a fourth stiffener forming the sill face.
15. The moment frame wall assembly of claim 1, wherein the shear panel comprises an integral, one-piece sheet metal panel, the one-piece sheet metal panel forming the upper edge margin attached to the header beam, the lower edge margin attached to the sill beam, the first side edge margin attached to the first column, and the second side edge margin attached to the second column.
16. The moment frame wall assembly of claim 1, wherein the shear panel comprises a first sheet metal panel and a second sheet metal panel, the first and second sheet metal panels arranged side-by-side and attached to one another.
17. The moment frame wall assembly of claim 16, wherein the first sheet metal panel forms the first side edge margin attached to the first column, a portion of the upper edge margin attached to the header beam, and a portion of the lower edge margin attached to the sill beam, and wherein the second sheet metal panel forms another portion of the upper edge margin attached to the header beam and another portion of the lower edge margin attached to the sill beam.
18. The moment frame wall assembly of claim 17, wherein the second sheet metal panel forms the second side edge margin attached to the second column.
19. The moment frame wall assembly of claim 18, further comprising first and second studs extending between the header and sill beams, the first and second sheet metal panels having portions sandwiched between the first and second studs.
20. The moment frame wall assembly of claim 1, wherein each yielding member of the beam-to-column joints constitutes a portion of either the header beam or the sill beam.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a front elevation of a conventional moment frame;
[0009] FIG. 2 is an enlarged, fragmentary view of a beam-to-column joint of the conventional moment frame;
[0010] FIG. 3 is an enlarged, fragmentary section of the conventional moment frame taken through line A-A of FIG. 2;
[0011] FIG. 4 is a perspective of the beam-to-column joint of FIG. 2;
[0012] FIG. 5 is a fragmentary elevation view of wood frame building showing a moment frame wall assembly according to one embodiment of the present disclosure;
[0013] FIG. 6A is a horizontal section of the moment frame wall assembly taken through line A-A of FIG. 5;
[0014] FIG. 6B is an enlarged, schematic, fragmentary section showing a connection between a shear panel and a moment frame of the moment frame wall assembly of FIG. 5;
[0015] FIG. 7 is an elevation view of the moment frame wall assembly;
[0016] FIGS. 8-18 are sections showing various connections between the shear panel and the moment frame according to other embodiments of the present disclosure;
[0017] FIG. 19 is a fragmentary section of a moment frame assembly according to another embodiment of the present disclosure;
[0018] FIG. 20 is an elevation view of a moment frame wall assembly according to another embodiment of the present disclosure;
[0019] FIG. 21 is an elevation view of a moment frame wall assembly according to another embodiment of the present disclosure;
[0020] FIG. 22 is a section showing a connection between adjacent sheet metal panels of the moment frame wall assembly of FIG. 21;
[0021] FIGS. 23-25 are sections showing various connections between adjacent sheet metal panels of the moment frame wall assembly of FIG. 21;
[0022] FIG. 26 is a schematic illustration illustrating the reaction forces in the moment frame wall assembly when subjected to an external lateral force;
[0023] FIG. 27 is a rendering of the deformation experienced by the moment frame wall assembly when subjected to an external lateral force;
[0024] FIG. 28 is a graph comparing the strength of a moment wall frame assembly according to the present disclosure, a conventional boxed wall frame, and a shear panel by itself; and
[0025] FIG. 29 is a graph comparing the strength of moment wall frame assemblies according to the present disclosure to the conventional moment frame.
[0026] Corresponding reference characters indicate corresponding parts throughout the drawings.
DETAILED DESCRIPTION
[0027] Referring to FIGS. 1-4, a conventional moment frame or boxed wall frame is generally indicated by reference numeral 10. The boxed wall frame 10 includes a pair of columns 12 (e.g., a first or left column and a second or right column) and a pair of beams 14 (e.g., a top or header beam and a bottom or sill beam) extending between and joining the columns at beam-to-column joints 16. Each beam-to-column joint 16 includes a panel zone 18. The structure and construction of the beam-to-column joint forces yielding behavior in the panel zone 18 so that the panel zone will absorb energy and fail before the beam 14 or the column 12 fails. As a result, components of the boxed wall frame 10 can be made of lighter weight construction, making them usable in wooden frame buildings to resist horizontal shearing forces (e.g., seismic or wind forces). The boxed wall frame 10 includes a beam-to-column joint 16 including a panel zone 18 at each corner of the wall frame. In the illustrated embodiment, the beams 14 are each generally identical and the columns are each generally identical. Likewise, the four beam-to-column joints 16 are all generally identical. Accordingly, one beam 14, one column 12 and one beam-to-column joint 16 will now be described with the understanding the description applies to each beam, each column, and each beam-to-column joint.
[0028] The beam 14 is a cold-formed steel (CFS) beam. In the illustrated embodiment, the beam 14 has a generally channel-shaped configuration, although the beam may have other shapes (e.g., C-section, Z-section, L-section, hat section, I-section, tubular section, rectangular hollow section, angles, etc. and combinations thereof) without departing from the scope of the present disclosure. The beam 14 includes a rear wall 20, top and bottom walls 22, 24 extending generally perpendicular from the rear wall, and top and bottom front wall portions 26, 28 extending generally perpendicular from the respective top and bottom walls in opposed facing relationship to the rear wall. A beam end channel 30 caps each end of the beam 14. Side stiffeners 32 extend along the top and bottom walls 22, 24 of the beam 14. The side stiffeners 32 can extend continuously along an entire length of the beam 14. The side stiffeners 32 can extend along only portions of the beam 14 (e.g., along portions adjacent the ends of the beam). The side stiffeners 32 are preferably attached by welds 34 to the top and bottom walls 22, 24 of the beam 14, although may be attached in other manners (e.g., bolts) without departing from the scope of the present disclosure. The side stiffeners 32 can be omitted. In the illustrated embodiment, the side stiffeners 32 are attached to the exterior surfaces or faces of the top and bottom walls 22, 24. In other embodiments, the side stiffeners may be attached to the interior surfaces or faces of the top and bottom walls.
[0029] The column 12 is a cold-formed steel column. In the illustrated embodiment, the column 12 has a generally channel-shaped configuration, although the column may have other shapes (e.g., C-section, Z-section, L-section, hat section, I-section, tubular section, rectangular hollow section, angles, etc. and combinations thereof) without departing from the scope of the present disclosure. The column 12 includes a rear wall 40, first and second side walls 42, 44 extending generally perpendicular from the rear wall, and first and second front wall portions 46, 48 extending generally perpendicular from the respective first and second side walls in opposed facing relationship to the rear wall. A column end channel 50 caps each end of the column 12. Side stiffeners 52 extend along the first and second side walls 42, 44 of the column 12. The side stiffeners 52 can extend continuously along an entire length of the column 12 or along only portions of the column. The side stiffeners 52 are preferably attached by welds 54 to the first and second side walls 42, 44 of the column 12, although may be attached in other manners (e.g., bolts) without departing from the scope of the present disclosure. The side stiffeners 52 can be omitted. In the illustrated embodiment, the side stiffeners 52 are attached to the exterior surfaces or faces of the side walls 42, 44. In other embodiments, the side stiffeners may be attached to the interior surfaces or faces of the side walls. In one embodiment, the column 12 may include a web stiffener (not shown) extending along the interior surface of the rear wall 40 to add additional strength to the column. The web stiffener extends from and between the beams 14 or the internal stiffeners 64 of the column (described below). In one embodiment, the web stiffener is a piece of structural steel having a thickness in the range of about to about , but may be formed of any other suitable material. The web stiffener can have any suitable shape (e.g., C-section, Z-section, L-section, hat section, I-section, tubular section, rectangular hollow section, angles, etc. and combinations thereof).
[0030] The beam 14 and column 12 are preferably formed of light gauge steel, such as 25-10 gauge steel. The side stiffeners 32, 52 are preferably metal plates (e.g., steel plates) having a thickness in the range of about to about , but may be formed of light gauge material or any other suitable material.
[0031] In the illustrated embodiment, the panel zone 18 is formed integrally with the beam 14 at an end thereof. The panel zone 18 includes reinforcing structure 60 configured to direct stresses within the panel zone. The panel zone 18 comprises a yielding member 71which comprises a portion of the beam 14 generally bounded by the reinforcing structure 60configured to fail prior to failure of the beam 14 and column 12 due to applied external lateral forces. Specifically, the reinforcing structure 60 is arranged to concentrate stresses to within a yielding member 71 so that the yielding member will yield or fail prior to failure of the beam and column due to external lateral forces. The panel zone 18 is at least partially bounded by the reinforcing structure 60. As illustrated, the reinforcing structure 60 includes multiple internal stiffeners 62 bounding the panel zone 18. A first internal stiffener 62a extends between the top and bottom walls 22, 24 of the beam 14 at a location spaced from the end of the beam and generally aligned with the second side wall 44 of the column 12. A second internal stiffener 62b (FIG. 4) extends between the top and bottom walls 22, 24 of the beam 14 at the end of the beam, generally aligned with the first side wall 42 of the column 12. A third internal stiffener 62c (FIG. 3) extends along the top wall 22 of the beam 14 in a direction between the first and second internal stiffeners 62a, 62b, and a fourth internal stiffener 62d (FIG. 3) extends along the bottom wall 24 of the beam in a direction between the first and second internal stiffeners. In the illustrated embodiment, the third and fourth internal stiffeners 62c, 62d extend between the first and second internal stiffeners 62a, 62b. The internal stiffeners 62 are preferably metal plates (e.g., steel plates) or metal shapes (e.g., channel, angle, tube) having a thickness required to force shear yielding of the panel zone 18. In one embodiment, the internal stiffeners are metal plates having a thickness in the range of about to about 1, such as about . The internal stiffeners 62 are connected to the beam 14, such as by stitch welding. In addition, the internal stiffeners 62 can be connected (e.g., welded) to each other. Optionally, the column 12 can also include an internal stiffener 64 extending between the first and second side walls 42, 44 adjacent the column end channel 50. The internal stiffener 64 is connected to the column 12, such as by stitch welding. The internal stiffener 64 is generally aligned with the internal stiffener 62d extending along the bottom wall 24 of the beam 14.
[0032] The beam 14 is attached to the column 12 with at least one fastener, such as attachment bolts 70. The attachment bolts extend through the bottom wall 24 of the beam 14 and the column end channel 50 to attach the beam to the column 12. The attachment bolts 70 also extend through the internal stiffeners 62d, 64 positioned adjacent the bottom wall 24 and the column end channel 50. The bottom wall 24 of the beam, the column end channel 50, and the internal stiffeners 62, 64 can include openings configured to receive the bolts 70. The bolts 70 are preferably high strength bolts, such as to 1 bolts. In one embodiment, the bolts 70 are 1 bolts. Other connection configurations and structures for attaching the beam 14 to the column 12 (not shown) may be used without departing from the scope of the present disclosure, such as angles and/or plates welded and/or bolted to the beam and the column.
[0033] The beam-to-column joint 16 is configured to yield to dissipate energy due to lateral loads. The panel zone 18 forces specific behavior of the beam 14 and column 12. The configuration of the beam and column assembly forces ductile behavior in a specific location (the panel zone 18) to dissipate energy and reduce the potential for failure of the entire assembly. Yielding (e.g., elastic deformation) occurs in the panel zone 18 before failure (e.g., plastic (i.e., permanent) deformation) of the beam 14 or column 12. In the illustrated embodiment, the yielding member 71 is a sheet metal panel, such as 25-10 gauge steel. Specifically, the yielding member 71 comprising a portion of the rear wall 20 of the beam 14 generally bounded by the stiffeners 62a, 62b, 62c, 62d will fail prior to failure of the column or beam, while the panel zone 18 remains sufficiently intact because of the stiffeners to support the weight of the building. Further details of this yielding, the boxed wall frame 16, and alternative embodiments of the boxed wall frame, and implementation of the boxed wall frame are described in U.S. Pat. No. 9,670,667, the entirety of which is hereby incorporated by reference.
[0034] Referring to FIGS. 5-7, one embodiment of a moment frame wall assembly according to one embodiment of the present disclosure is generally indicated at 110. The moment frame wall assembly 110 includes a moment frame and a shear panel 112. In the illustrated embodiment, the moment frame of the moment frame wall assembly 110 is the boxed wall frame 10 of FIG. 1-4, although other types and/or configurations of moment frames can be used without departing from the scope of the present disclosure. The shear panel 112 and the boxed wall frame 10 work together to resist applied external lateral forces or loads.
[0035] The shear panel 112 is attached to the boxed wall frame 10. The shear panel 112 includes a generally vertical shear wall 114. The shear wall 114 generally fills or blocks (e.g., overlaps) the opening between the beams 14 and columns 12 of the boxed wall frame 10. The shear panel 112 has a generally rectangular shape. The shear panel 112 includes a plurality of edge margins that are attached to the beams 14 and columns 12 of the boxed wall frame 10. The shear panel 112 includes an upper edge margin 116A attached to the header beam 14, a lower edge margin 116B attached to the sill beam 14, a first side edge margin 116C attached to the first column 12, and a second side edge margin 116D attached to the second column 12. The edge margins 116A-D generally extend around (e.g., form) the perimeter of the shear panel 112. The shear wall 114 can form at least a portion of the edge margins 116A-D. In this embodiment, the moment frame wall assembly 110 includes a plurality of elongate members used to facilitate the connection between the edge margins 116A-D and the boxed wall frame 10. The moment frame wall assembly 110 includes a first elongate member 118A used in the connection between the upper edge margin 116A and the header beam 14, a second elongate member 118B used in the connection between the lower edge margin 116B and the sill beam 14, a third elongate member 118C used in the connection between the first side edge margin 116C and the first column 12, and a fourth elongate member 118D used in the connection between the second side edge margin 116D and the second column 12.
[0036] With reference to FIGS. 6A-B, the connections between each edge margin 116A-D and its respective beam 14 or column 12 are all generally identical. Accordingly, one connection will now be generally described with the understanding the description applies to each connection. The elongate member 118A-D extends along its respective beam 14 or column 12, preferably along the entirety of or substantially the entirety of the distance between the columns or between the beams. The elongate member 118A-D may comprise a single member or piece or may be made up of multiple members or pieces spaced apart along the respective beam 14 or column 12. The elongate member 118A-D forces or compresses the respective edge margin 116A-D of the shear panel 112 against the respective beam 14 or column 12. In this embodiment, the shear panel 112 includes a top wall 120A, a bottom wall 120B, a first side wall 120C, and a second side wall 120D. As illustrated, the top wall 120A, bottom wall 120B and first and second side walls 120C, 120D are formed by bending over edge margins of the shear panel 112 so that the top wall, bottom wall and side walls extend generally perpendicular to the shear wall 114. In this embodiment, each edge margin 116A-D is formed by a portion of the shear wall 114 and one of the top, bottom, first side, and second side walls 120A-D. Each of the top, bottom, first side, and second side walls 120A-D extend from the shear wall 114. Each of the top, bottom, first side, and second side walls 120A-D are generally perpendicular to the shear wall 114.
[0037] Each elongate member 118A-D forces or compresses its corresponding top, bottom, first side, and second side walls 120A-D of the shear panel 112 against its respective beam 14 or column 12. Specifically, each of the top, bottom, first side, and second side walls 120A-D of the shear panel 112 overlaps and engages a face 126A-D of is corresponding beam 14 or column 12. In this embodiment, each face 126A-D is an interior-facing face (that bounds the opening of the boxed wall frame 10). The faces 126A-B of the beams 14 face toward each other and each face in a direction parallel to a height of the boxed wall frame 10. The faces 126C-D of the columns 12 face toward each other and each face in a direction parallel to a length of the boxed wall frame 10. In the illustrated embodiment, each face 126A-D is formed by one of the stiffeners 32, 52 of the beam 14 or column 12. As shown in FIG. 6B, each edge margin 116A-D generally wraps around its corresponding elongate member 118A-D. Each elongate member 118A-D includes a first face 122A-D and a second face 124A-D. The first faces 122A-D of each elongate member 118A-D are all generally parallel to a vertical plane. As illustrated, the first faces 122A-D are generally coplanar. The shear wall 114 overlaps and engages each first face 122A-D of each elongate member 118A-D. The second faces 124A-B of the first and second elongate members 118A-B are generally horizontal and the second faces 124C-D of the third and fourth elongate member 118C-D are generally vertical. Each of the top, bottom, first side, and second side walls 120A-D overlap and engage the corresponding second face 124A-D of its corresponding elongate member 118A-D. Wrapping the edge margins 116A-D of the shear panel 112 around the elongate members 118A-D, and using the elongate members to compress at attach the shear panel to the columns 12 and beams 14 helps prevent the edge margins from disconnecting from their respective beams 14 or columns 12 when the moment frame wall assembly is subject to the external lateral forces. More specifically, the attachment of the shear panel 112 to the columns 12 and beams 14 in this manner avoids stress concentrations in the shear panel which would tear it away from the beam or column. As a result, relatively large loads can be transferred between the columns 12 and beams 14, and the shear panel 112 without premature failure of a connection between the columns and beams, and the shear panel. Preferably, the first and second faces 122A-D, 124A-D of each elongate member 118A-B are connected by a rounded surface (e.g., rounded bend, fillet, etc.), which provides a smooth transition to transfer the tensile forces developed in the shear wall 114 to the top, bottom, first side, and second side walls 120A-D.
[0038] In the illustrated embodiment, the elongate members 118A-D comprise a metal (e.g., steel) angle, with one leg of the angle forming the first face 122A-D and the other leg of the angle forming the second face 124A-D. The thickness of the legs may be in the range of about to about . In other embodiments, the elongate members 118A-D comprise a metal (e.g., steel) plate having a thickness in the range of about to about . In this embodiment, the elongate members 118A-D do not have the first face 122A-D. In other embodiments, the elongate members 118A-D are formed of light gauge steel, such as 10-25 gauge steel. Other configurations of the elongate members 118A-D may be used without departing from the scope of the present disclosure. For example, the elongate members 118A-D may have a C cross-sectional shape or a rectangular, hollow cross-sectional shape. Moreover, not all connections between the shear panel and the beams or columns must be the same.
[0039] Referring to FIG. 7, each connection includes a series or plurality of fasteners (e.g., bolts). Each series of fasteners 128A-D connects one of the edge margins 116A-D, its corresponding elongate member 118A-D, and its corresponding beam 14 or column 12 together. In other words, each series of fasteners 128A-D attaches its corresponding edge margin 116A-D to its corresponding beam 14 or column 12. In this embodiment, each fastener in the series of fasteners 128A-D extends through one of the stiffeners 32, 52 of the corresponding beam 14 or column 12. This allows the fasteners to directly transfer the developed tensile forces in the shear panel 112 to stiffeners 32, 52, particularly a stiffener 32 of each beam 14. The stiffeners 32 of the beams 14 form a main part of the load path between the applied external lateral forces and the developed tensile forces in the shear panel 112 that resist the applied external lateral forces. The fasteners in each series 128A-D are spaced apart from one another, preferably by a set distance such as by about 4-inches to 12-inches depending upon the size of the fastener. For example, larger fasteners are stronger and can have larger spacing therebetween. Preferably, each series of fasteners 128A-D (e.g., the fasteners at each end of the series) are spaced apart from their corresponding interior corners 17 of the boxed wall frame 10 (the corresponding interior corners being the two interior corners the series of fasteners is disposed between). Each interior corner 17 is formed by one of the columns 12 and one of the beams 14 (e.g., a first interior corner is formed by the first column and the header beam, a second interior corner is formed by the second column and the header beam, etc.). In one embodiment, the fastener at each end of the series 128A-D is spaced apart from its corresponding interior corner 17 by a distance that is about half the distance between adjacent fasteners of the series. Each series of fasteners 128A-D spreads the tensile forces that develop in the shear panel 112 in response to the external lateral forces over a greater area (e.g., most of the height of column and length of the beam), instead of having the force be concentrated at a single point (which would then require more structural reinforcement at this point), such as in conventional structural steel braced frames. Further, spacing the series of fasteners 128A-D from the interior corners 17 prevents the tensile forces developed in the shear panel from being transferred directly to the interior corners, which are the points of highest stress in the boxed wall frame 10 (when the external lateral forces are applied), and facilitates the spreading out of the developed tensile forces by transferring tensile forces over a greater number of fasteners. The fasteners are preferably bolts, such as high-strength bolts, although other types of fasteners (e.g., screws) may be used without departing from the scope of the present disclosure.
[0040] Other ways of connecting the shear panel 112 to the boxed wall frame 10, some of which are described herein, may be used without departing from the scope of the present disclosure. For example, the shear panel 112 may be welded to the boxed wall frame along each edge margin 116A-D to the respective column 12 or beam 14. The welds may be continuous welds or a series of spaced apart welds.
[0041] FIG. 8 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIGS. 6A-B, except that the elongate members 118A-D are light gauge steel members (illustrated as having a C-shaped cross-section) and the fasteners 128A-D are screws (e.g., self-tapping screws), instead of bolts. Because screws are not as strong at bolts, the connection may include more screws than the number of bolts in the connection illustrated in FIGS. 6A-B described above. In addition, the connection includes another set of fasteners 129A-D that extend through the shear wall 114 and the elongate member 118A-D (e.g., the first face 122A-D) to connect the two together.
[0042] FIGS. 9A-B illustrate another way of connecting the shear panel 112 to the boxed wall frame 10. In this embodiment, the shear panel 112 does not include the top, bottom, first side, and second side walls 120A-D. Instead, the shear panel 112 (specifically, the shear wall 114) just overlaps and engages the first faces 122A-D of the elongate member 118A-D. Each elongate member 118A-D (e.g., the second faces 124A-D thereof) engages the face 126A-D of is corresponding beam 14 or column 12. The elongate members 118A-D may be attached to their corresponding beam 14 or column 12 via the series of fasteners 128A-D (e.g., bolts) as described above. Alternatively, the elongate members 118A-D may be attached to their corresponding beam 14 or column 12 via welding or screws (e.g., self-tapping screws). Similarly, the edge margins 116A-D of the shear panel 112 may be attached to their corresponding elongate member 118A-D with a series of fasteners (e.g., bolts), similar to the series of fasteners 128A-D described above. Alternatively, the edge margins 116A-D of the shear panel 112 may be attached to their corresponding elongate member 118A-D via welding or screws (e.g., self-tapping screws), similar to the fasteners 129A-D described above.
[0043] FIG. 10 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIGS. 9A-B, except that the elongate members 118A-D are light gauge steel members (illustrated as having a C-shaped cross-section).
[0044] FIG. 11 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIGS. 9A-B, except that the shear wall 114 is further extended to overlap and engage both elongate members 118A-D and side faces 130A-D of the beams 14 and columns 12. Fasteners or welds, as described herein, may be used to attach the edge margins 116A-D of the shear panel 112 to their corresponding elongate member 118A-D. The elongate members 118A-D take the form of angle irons (e.g., L-shaped) in this version. Likewise, fasteners or welds, as described herein, may be used to attach the portion of the edge margins 116A-D overlapping the side faces 130A-D to their corresponding beam 14 or column 12.
[0045] FIG. 12 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIG. 11, except that welds 133A-D (e.g., plug welds) are used to attach the portion of the edge margins 116A-D overlapping the side faces 130A-D to their corresponding beam 14 or column 12 and are used to attach the portion of the edge margins 116A-D to the elongate members 118A-D. In addition, welds 135A-D are used to attach the elongate members 118A-D to their corresponding beams 14 or columns 12.
[0046] FIG. 13 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIG. 11, except that the elongate members 118A-D are light gauge steel members (illustrated as having a C-shaped cross-section). The connection includes a set of fasteners 129A-D used to attach the portion of the edge margins 116A-D overlapping the elongate members 118A-D to the elongate members. In addition, the connection includes another set of fasteners 131A-D used to attach the portion of the edge margins 116A-D overlapping the side faces 130A-D to their corresponding beam 14 or column 12.
[0047] FIG. 14 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIG. 13, except that the elongate members 118A-D are omitted.
[0048] FIG. 15 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIG. 14, except that welds 133A-D (e.g., plug welds) are used to attach the portion of the edge margins 116A-D overlapping the side faces 130A-D to their corresponding beam 14 or column 12. The light gauge steel member (yellow) shown in FIG. 15 can be omitted or may be part of the infill wall (e.g., a header or sill or one of the studs 136) that the studs 136 (described below) are a part of. The light gauge steel member is not attached to the shear panel 112.
[0049] FIG. 16 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIGS. 6A-B. In this embodiment, the shear panel 112 wraps further around the elongate members 118A-D. Each elongate member 118A-D includes a third face 132A-D. In the illustrated embodiment, the third face 132A-D is generally parallel to the first face 122A-D. Likes the first faces 122A-D, the third faces 132A-D are all generally vertical and may also be generally coplanar with one another. The illustrated elongate member 118A-D in FIG. 11 has a C cross-sectional shape to have the third face 132A-D. In this embodiment, the shear panel 112 further includes a first back wall 134A, a second back wall 134B, a third back wall 134C, and a fourth back wall 134D. In this embodiment, each edge margin 116A-D is formed by a portion of the shear wall 114 and one of the top, bottom, first side, and second side walls 120A-D, and one of the back walls 134A-D. The first back wall 134A extends from the top wall 120A, the second back wall 134B extends from the bottom wall 120B, the third back wall 134C extends from the first side wall 120C, and the fourth back wall 134D extends from the second side wall 120D. Each of the back walls 134A-D are generally parallel to the shear wall 114 and generally perpendicular to the top, bottom, first side, and second side walls 120A-D. Each of the back walls 134A-D overlap and engage the corresponding third face 132A-D of its corresponding elongate member 118A-D.
[0050] FIG. 17 illustrates another way of connecting the shear panel 112 to the boxed wall frame 10. This connection is similar to the connection illustrated in FIGS. 6A-B. In this embodiment, the material (e.g., sheet metal) that forms the top, bottom, first side, and second side walls 120A-D is bent back on itself. As a result, the top, bottom, first side, and second side walls 120A-D of FIG. 12 are twice as thick as the top, bottom, first side, and second side walls 120A-D of FIGS. 6A-B. Further, in this embodiment, the elongate members 118A-D comprise a metal plate. The edge margins 116A-D bending around an edge of the metal plate 118A-D. As a result, the shear panel 112 engages the edge (e.g., edge surface) of the metal plate and is sandwiched between the metal plate 118A-D and the stiffeners 32, 52 of the box frame 10.
[0051] FIG. 18 illustrates another way of connecting the shear panel 112 to the boxed wall frame. This connection is similar to the connection illustrated in FIG. 17, except the material (e.g., sheet metal) that forms the top, bottom, first side, and second side walls 120A-D is only a single layer (i.e., not bent back on itself).
[0052] In FIGS. 8-18, only one or two of the connections between the edge margins 116A-D of the shear panel 112 and its respective beam 14 or column 12 are shown. However, for each embodiment of the connections illustrated in FIGS. 8-18, the connections between each edge margin 116A-D and its respective beam 14 or column 12 are all generally identical. Accordingly, it is understood that for each embodiment of the connections in FIGS. 8-18, the embodiment's figure(s) and corresponding description generally apply to each connection between each edge margin 116A-D and its respective beam 14 or column 12.
[0053] Referring back to FIGS. 5-7, the shear panel 112 fits within the profile (e.g., opening) of the boxed wall frame 10. Thus, the shear panel 112 does not meaningfully increase the thickness of the moment frame wall assembly 110 compared to the boxed wall frame 10 alonethe thickness is only increased by the thickness of the shear wall 114. Conventional lateral resisting systems, such as bracing, that would be applied to a conventional boxed wall frame can undesirably meaningfully increase the thickness of the overall system. In addition, the shear panel 112 allows infill studs 136 to be mounted in the opening of the boxed wall frame 10. The infill studs 136 generally extend between the header and sill beams 14. The infill studs 136 are non-structural and are there to facilitate the completion of the aesthetics of the wall. For example, drywall (not shown) can be mounted to the moment frame wall assembly 110 by fastening the drywall to the infill studs 136. The infill studs 136 may be formed from light gauge metal. If desired, the infill studs 136 may be attached to the shear panel 112 with fasteners (e.g., self-tapping screws). The infill studs 136 can be omitted. The infill studs 136 may be part of an infill wall which may further include a header capping the tops of the infill studs and a sill capping the bottoms of the infill studs. The header and sill may be attached to the header and sill beams 14, respectively, as described herein. The header and sill may have generally the same construction and shape as the infill studs 136. The infill wall can be omitted.
[0054] The shear panel 112 comprises a sheet metal panel. In this embodiment, the shear panel 112 comprises an integral, one-piece sheet metal panel. For example, the shear panel 112 can be stamped or cut from a single piece of sheet metal and then bent into shape (for those embodiments employing bends in the shear panel). Thus, the one-piece sheet metal panel forms the upper edge margin 116A attached to the header beam 14, the lower edge margin 116B attached to the sill beam 14, the first side edge margin 116C attached to the first column 12, and the second side edge margin 116D attached to the second column 12. In one embodiment, the shear panel 112 is formed of light gauge steel, such as 25-10 gauge steel, or more preferably 22-24 gauge steel. The light gauge shear panel 112 is easier to handle and install than conventional braced systems.
[0055] Referring to FIGS. 5-7 and to FIGS. 26 and 27, the shear panel 112 is configured to resist the external lateral forces applied to the moment frame wall assembly 110. As shown in FIGS. 26 and 27, because the shear panel 112 is attached to each of the columns 12 and the beams 14 of the boxed wall frame 10, the shear panel resists the lateral movement of the beams 14 relative to one another due to the applied external lateral forces. The ductility of the shear panel 112 (specifically, the shear wall 114) enables one or more tension struts 113 to form in the shear wall 114 upon the application of the external lateral force to resist the lateral movement of the beams 14 relative to one another. The tension struts 113 form due to the shear wall 114 deflecting (e.g., elastic deformation) due to the relative movement of the beams 14 upon the application of the external lateral force. The exclusive formation of tension struts 113 is due to the inability to shear panel 112 to develop compression struts. The tension struts 113 extend at an angle relative to the height and length of the boxed wall frame 10 (or extend generally between diagonally opposing corners of the individual panels 112A-C when multiple pieces make up the shear panel 112, as described herein). The tension struts are generally parallel to an imaginary axis extending between diagonally opposite interior corners 17 of the boxed wall frame 10. Since the shear panel 112 is attached to the each of the columns 12 and the beams 14 along generally the entire length and height of the shear panel, the tension struts 113 generally form across the entirety of the shear wall 114. This spreads the tensile forces developed in the shear wall 114 that resist the external lateral force over a greater area, generally the entire length and height of the shear panel 112, thereby preventing the formation of large point loads. This allows the shear panel 112 to be of light gauge construction (e.g., light gauge steel), instead of the large and bulky structural steel used in conventional braces. The ribbons or waves in the shear wall 114 in FIG. 27 generally illustrate the tension struts 113 that form when the shear wall yields or elastically deforms (the directionality of the yielding of the shear wall is shown by the shading in FIG. 27, the darker the shading the greater the amount of yielding of the shear panel 112 in the direction orthogonal to the tension strut 113). Further, the ductility of the shear panel 112 allows the shear panel to resist lateral forces applied in either lateral direction and allows the shear panel to develop the tension struts 113 resisting lateral loads in one direction and then quickly develop tension struts for resisting lateral loads in another (opposite) direction if the direction of the lateral force changes, such as during an earthquake. In other words, the shear panel 112 can elastically deform in one manner and then quickly recover and elastically deform in a different manner if the direction of the applied external lateral force changes. Conventional brace systems are not as ductile and are therefore more prone to buckling.
[0056] The shear panel 112, preferably, is configured to yield with the yielding members 71 of the beam-to-column joints 16 of the boxed frame 10 (broadly, is configured to yield with at least some of the yielding members). As a result, the shear panel 112 and the yielding members 71 of the beam-to-column joints 16 (broadly, the boxed wall frame 10) work simultaneously to resist the external lateral forces applied to the moment frame wall assembly 110. Thus, as shown in FIG. 26, the moment frame wall assembly 110 has two yielding mechanisms for resisting the applied external lateral forces: (1) the yielding members 71 of the boxed wall frame 10 and (2) the shear wall 114. These two mechanism work in concert together, thereby increasing the total amount of lateral force that can be resisted by the moment frame wall assembly 110 over the conventional boxed wall frame alone. For example, FIG. 28 is a graph comparing the relative strengths of a moment frame wall assembly according to the present disclosure, the strength of a conventional boxed wall frame, and the strength of a sheet metal shear panel by itself. More specifically, FIG. 28 plots normalized base shear supported by these respective systems as a function of the amount of story drift in a building during a lateral force event (e.g., an earthquake). The shear strength of the conventional boxed wall frame is indicated by line 400 (black broken line). The shear strength of a sheet metal shear panel by itself is indicated by line 402 (blue line). The shear strength of the moment frame wall assembly according to the present disclosure is indicated by line 404. As shown by the graph in FIG. 28, the shear strength of the moment frame wall assembly is greater than both the shear strength of the conventional boxed wall frame and the shear strength of the sheet metal shear panel by itself. This indicates the boxed wall frame 10 and the shear panel 112 of the moment frame wall assembly work together, simultaneously and synergistically, to resist the lateral forces. Overall, the moment frame wall assembly of the present disclosure is able to resist about 25%-40% larger lateral force compared to the conventional boxed wall frame.
[0057] In another example, FIG. 29 is a graph comparing the strength of different variations of a moment frame wall assembly 110 according to the present disclosure to a conventional boxed wall frame. More specifically, FIG. 29 plots base shear supported by the moment frame wall assembly 110 as a function of the amount of story drift in a building during a lateral force event (e.g., an earthquake). The shear strength of the conventional boxed wall frame is approximated by line 500 (blue broken line). The shear strength of one version of a moment frame wall assembly 110 according to the present disclosure with a shear panel 112 formed from 22 gauge sheet metal and no infill studs is indicated by line 502 (red line). The shear strength of another version of a moment frame wall assembly 110 according to the present disclosure with infill studs and a shear panel 112 formed from multiple pieces of 22 gauge sheet metal that are continuously welded together along vertical seams is indicated by line 504 (green line). The shear strength of another version of a moment frame wall assembly 110 according to the present disclosure with infill studs and a shear panel 112 formed from multiple pieces of 22 gauge sheet metal that are welded together by 6-inch spaced apart welds along vertical seams is indicated by line 506 (blue line). As shown in FIG. 29, the shear strength of the versions of the moment wall frame assemblies 110 is stronger (able to resist larger lateral forces) than the conventional boxed wall frame.
[0058] In general, the yielding sequence of the moment wall frame assembly 110 upon the application of an external lateral load is as follows: (1) yielding of the shear panel 112, (2) yielding of the yielding members 71, (3) yielding of the columns 12, and (4) tearing of the shear panel 112 (which will generally occur at the connections with the boxed wall frame 10). Once one component starts yielding, it continues to yield as other components start to yield. Thus, while the shear panel 112 may yield first, it is still yielding when the yielding members 71 also start to yield. In other words, the arrangement of the moment wall frame assembly 110 (specifically, the arrangement of the shear panel 112 and the yielding members 71) results in the shear panel 112 starting to yield before the yielding members 71. Further, this offset in the time the shear panel 112 begins to yield and the time the yielding members 71 begin to yield allows the moment wall frame assembly 110 to resist a lateral load close to the peak strength of the moment wall frame assembly for a longer period of time (e.g., over a greater length of story drift). This results in the moment wall frame assembly 110 having a plateau shape at the top of its force-displacement curve while a shear panel by itself has a drop in resistance due to failure at connections (see line 402 in FIG. 28, the shear force resisted by the sheet metal shear panel ends at a story drift of about 4.5 inches because of failure at the connections compared to the moment wall frame assembly 110 which is still providing resistance (see line 404)). This means the moment wall frame assembly of the present disclosure has a higher ductility than a sheet metal shear panel alone.
[0059] If the two yielding mechanism did not work simultaneously, one yielding mechanism (e.g., the yielding members 71) would first resist the external lateral forces and have to fail before the other yielding mechanism (e.g., the shear panel 112) would then resist the external lateral force. This leads to inefficiencies as only one yielding mechanism is resisting the lateral forces at a time, which prevents the two yielding mechanisms from combining to increase the overall strength and ductility of the system. Instead, the amount of lateral force the system could resist is equal to the strength of the stronger of the two yielding mechanisms. In addition, when the yielding mechanism (which first resists the external lateral forces) fails, the resistance to the lateral force will all be transferred to the second yielding mechanism. If the second yielding mechanism is not stronger than the first yielding mechanism, than the second yielding mechanism will immediately fail. This results in the second yielding mechanism being completely irrelevant and a waste of time and materials. Because the shear panel 112 and the yielding members 71 of the present disclosure work together, the moment frame wall assembly 110 of the present disclosure does not have these inefficiencies. Moreover, because the shear panel 112 is make of light gauge metal, it is an inexpensive option for increasing the lateral strength of conventional boxed wall frames, compared to conventional systems such as lateral bracing.
[0060] In one embodiment, the thickness of the shear panel 112 (specifically, the shear wall 114) is within about 30%-40% of the thickness of the yielding members 71. In the illustrated embodiment, the sheet metal panel (e.g., shear wall 114) of the shear panel 112 has a thickness less than or equal to the thickness of the sheet metal panel of the yielding members 71 of the boxed wall frame 10. For example, in one embodiment, the sheet metal panel of the yielding member 71 is 12 gauge and the shear panel 112 is 22 gauge. This relationship in thicknesses between the yielding members 71 and the shear panel 112 ensures these components will yield simultaneously to resist applied lateral forces together. If one of these components where significantly stronger than the other, then these component would not yield simultaneously but one after another, thereby defeating the benefit of having two yielding mechanisms for the reasons described herein.
[0061] The moment wall frame assembly of the present disclosure uses the shear panel 112 to get the higher stiffness (and therefore to reduce the drift, which is critical to lateral design of buildings, particularly to limit earthquake/wind damage) while using the boxed wall frame 10 to maintain the necessary ductility. The increased level of ductility provides an additional layer of energy absorption and maintains increased protection from premature failure of the building. The increased ductility means that the assembly can maintain a load close to a peak load for a period of time (or drift) before the assembly starts to lose the resistance. This is shown in FIG. 28 by the close to a plateau shape at the top of the force-displacement curve. Having the increased ductility and therefore being able to main a resistance for a longer time/drift, provides building occupants more time and better chance to leave the building before it collapses due to excessive lateral loads, such as during an earthquake.
[0062] The moment frame wall assembly 110 can be sold and shipped to customers as a disassembled kit, or alternatively, the moment frame wall assembly 110 can be sold and shipped to customers in a partially for fully assembled state (e.g., as seen in FIGS. 5 and 7). Prefabricating the moment frame wall assembly 110 can eliminate installation errors and reducing or eliminating variability in performance. The moment frame wall assembly 110 is useful in commercial and residential construction of wood (mass timber and light-frame) and light-frame cold form steel construction, such as single family and multi-family residences. Multiple moment frame wall assemblies 110 can be used in the construction of a building. If the moment frame wall assemblies 110 are shipped to a construction site already assembled, the possibility of miscalculation or incorrect connection in the field is reduced. In addition, the moment frame wall assembly 110 can be dropped into a building and secured in place without requiring field assembly (e.g., welding). The moment frame wall assembly 110 is simply secured into place in the building with bolts or screws.
[0063] In use, each moment frame wall assembly 110 is placed in position on a wall of a building. Referring to FIG. 5, the column 12 of the moment frame wall assembly 110 may be positioned alongside a column (e.g., wood column, composite wood column (such as a glulam column), etc.) of the building. On the first level of the building, the moment frame wall assembly 110 is positioned to contact and engage the foundation of the building. The bottom beam 14 is attached to the foundation with tie-down rods 104. As illustrated, a tie-down rod 104 is attached to each side of the moment frame wall assembly 110. In addition, fasteners 106 (see, FIG. 1) may also attach the bottom beam 14 to the foundation. In a multi-level building (FIG. 5), multiple moment frame wall assembly 110 can connected together in a vertical stack. The moment frame wall assembly 110 may be directly stacked one on top of another (e.g., a bottom beam 14 sits on a top beam 14) or two adjacent boxed wall frames may be separated by a floor system (e.g., cross-laminated timber (CLT) floor) sandwiched there-between (e.g., a bottom beam 14 sits on the floor and the floor sits on the top beam 14). Tie down rods 104 attach two adjacent stacked moment frame wall assembly 110 together in the multi-level building.
[0064] Referring to FIG. 19, another embodiment of a moment frame wall assembly according to the present disclosure is generally indicated at reference numeral 210. The moment frame wall assembly 210 of FIG. 19 is generally analogous to the moment frame wall assembly 110 of FIGS. 5-12 and, thus, for ease of comprehension, where similar, analogous or identical parts are used, identical reference numerals are employed. Accordingly, unless clearly stated or indicated otherwise, the above descriptions regarding the moment frame wall assembly 110 of FIGS. 5-12 also apply to the moment frame wall assembly 210 of FIG. 19.
[0065] In this embodiment, the moment frame wall assembly 210 includes two boxed wall frames 10 placed back-to-back with the shear panel 112 sandwiched therebetween. The shear panel 112 does not include the top, bottom, first side, and second side walls 120A-D. Instead, the shear panel 112 (specifically, the shear wall 114) overlaps, engages, and is sandwiched between the first faces 122A-D of the elongate members 118A-D for each boxed wall frame 10 and the side faces 130A-D of the beams 14 and columns 12 of each boxed wall frame. Fasteners or welds, as described herein, may be used to attach the edge margins 116A-D of the shear panel 112 to their corresponding elongate member 118A-D. For example, self-tapping screws may extend through the shear panel 112 and the elongate members 118A-D on each side of the shear panel. Likewise, fasteners or welds, as described herein, may be used to attach the portion of the edge margins 116A-D overlapping the side faces 130A-D to their corresponding beam 14 or column 12. For example, self-tapping screws may extend through the shear panel 112 and the rear walls 20, 30 of the beams 14 or columns 12, respectively, on each side of the shear panel. In one embodiment, the shear panel 112 overlaps a majority of the side faces 130A-D, or more preferably substantially all of the side faces 130A-D.
[0066] In FIG. 19, only one connections between the edge margins 116A-D of the shear panel 112 and its respective beam 14 or column 12 is shown. However, for the moment frame wall assembly 210 of FIG. 19, the connections between each edge margin 116A-D and its respective beams 14 or columns 12 are all generally identical. Accordingly, it is understood that for the connection in FIG. 19, the figure and corresponding description generally applies to each connection between each edge margin 116A-D and its respective beams 14 or columns 12.
[0067] Referring to FIGS. 20-21, another embodiment of a moment frame wall assembly according to the present disclosure is generally indicated at reference numeral 310. The moment frame wall assembly 310 of FIGS. 20-21 is generally analogous to the moment frame wall assembly 110 of FIGS. 5-18 and, thus, for ease of comprehension, where similar, analogous or identical parts are used, identical reference numerals are employed. Accordingly, unless clearly stated or indicated otherwise, the above descriptions regarding the moment frame wall assembly 110 of FIGS. 5-18 also apply to the moment frame wall assembly 310 of FIGS. 20-21.
[0068] In this embodiment, the shear panel 112 is comprises a plurality of sheet metal panels (broadly, panel sections) that are joined together to form the overall shear panel. For example, FIG. 20 illustrates the shear panel 112 comprising two sheet metal panels 112A-B and FIG. 21 illustrates the shear panel 112 comprising three sheet metal panels 112A-C. The sheet metal panels 112A-C are arranged side-by-side and attached to one another. In other embodiments, the sheet metal panels may be stacked one-on-top of another. When joined together, the sheet metal panels 112A-C form the components (e.g., edge margins 116A-D, shear wall 114) of the shear panel 112 described herein. For example, the sheet metal panels 112A-C form the edge margins 116A-D that are attached to the beams 14 and columns 12. In the embodiment illustrated in FIG. 20, the first sheet metal panel 112A forms the first side edge margin 116C attached to the first column 12, a portion of the upper edge margin 116A attached to the header beam 14, and a portion of the lower edge margin 116B attached to the sill beam 14. The second sheet metal panel 112B forms another portion (e.g., the rest of) of the upper edge margin 116A attached to the header beam 14, another portion (e.g., the rest of) of the lower edge margin 116B attached to the sill beam 14, and the second side edge margin 116D attached to the second column 12. In the embodiment illustrated in FIG. 21, the first sheet metal panel 112A forms the first side edge margin 116C attached to the first column 12, a portion of the upper edge margin 116A attached to the header beam 14, and a portion of the lower edge margin 116B attached to the sill beam 14. The second sheet metal panel 112B forms another portion of the upper edge margin 116A attached to the header beam 14 and another portion of the lower edge margin 116B attached to the sill beam 14. The third sheet metal panel 112C forms another portion (e.g., the rest of) of the upper edge margin 116A attached to the header beam 14, another portion (e.g., the rest of) of the lower edge margin 116B attached to the sill beam 14, and the second side edge margin 116D attached to the second column 12.
[0069] In one embodiment, as shown in FIG. 20, each sheet metal panel 112A-C may be part of a pre-formed or prefabricated unit (e.g., a panel section assembly). The pre-formed unit may include elongate members 118A-c (or portions thereof) attached to the sheet metal panel (such as with screws or welds). In this embodiment, some or all of the elongate members 118A-D may comprise two or more separate pieces. For example, in the embodiment illustrated in FIG. 20, a portion or section 118A of the first elongate member 118A is attached to the first sheet metal panel 112A, a portion or section 118B of the second elongate member 118B is attached to the first sheet metal panel 112A, and the third elongate member 118C is attached to the first sheet metal panel. Similarly, another portion or section 118A (e.g., the rest of) of the first elongate member 118A is attached to the second sheet metal panel 112B, another portion or section 118B (e.g., the rest of) of the second elongate member 118B is attached to the second sheet metal panel 112B, and the fourth elongate member 118D is attached to the second sheet metal panel. In the embodiment illustrated in FIG. 21, a portion or section 118A of the first elongate member 118A, a portion or section 118B of the second elongate member 118B, and the third elongate member 118C are attached to the first sheet metal panel 112A. Another portion or section 118A of the first elongate member 118A and another portion or section 118B of the second elongate member 118B are attached to the second sheet metal panel 112B. Another portion or section 118A (e.g., the rest of) of the first elongate member 118A, another portion or section 118B (e.g., the rest of) of the second elongate member 118B, and the fourth elongate member 118D are attached to the third sheet metal panel 112C. The pre-formed unit may also include the infill studs 136 also attached to the sheet. The pre-formed unit can then be positioned and attached to (e.g., fastened) the boxed wall frame 10 as described herein. Attaching the infill studs 136 and elongate members 118A-D (or the portions thereof) to create pre-formed units allows the pre-formed unit to be pre-assembled (e.g., assembled offsite) and then quickly installed in the boxed wall frame 10. In other embodiments, the sheet metal panels 112A-B and the elongate members 118A-D are installed as separate pieces (e.g., no pre-attachment to one another) to the boxed wall frame 10.
[0070] Referring to FIG. 22, in the illustrated embodiment, the adjacent sheet metal panels 112A-C are attached together by having portions thereof sandwiched between the two (e.g., first and second) infill studs 136. Instead of infill studs 136, elongate members similar to the elongate members 118A-D described herein could also be used. Each sheet metal panel 112A-C includes at least one side wall 138 (similar to the side walls 120C-d described herein) that is sandwiched between the infill studs 136. As shown in FIG. 22, the side walls 138 of two adjacent sheet metal panels 112A-B are sandwiched between two infill studs 136. A series of fasteners 140 (e.g., bolts) extend through the side walls 138 of the two adjacent sheet metal panels 112A-B and the infill studs 136 (e.g., walls thereof) to attach the two adjacent sheet metal panels together. The series of fasteners 140 may be spaced in the same manner as the series of fasteners 128A-D, described herein. This direct connection of the sheet metal panels 112A-B with one another enables the sheet metal panels 112A-C to act cohesively when resisting external lateral forces. For example, this connection allows for the development of the tension struts 113 within the shear panel 112, across one or more of the sheet metal panels 112A-C, upon the application of an external lateral load. Other ways of attaching the sheet metal panels 112A-C together may be used without departing from the scope of the present disclosure. For example, the sheet metal panels 112A-C may be welded together, such as with a continuous weld or a series of spaced apart welds.
[0071] FIG. 23 illustrates another way of connecting the sheet metal panels 112A-C together. This connection is similar to the connection illustrated in FIG. 23, except that the fasteners 140 are screws (e.g., self-tapping screws).
[0072] FIG. 24 illustrates another way of connecting the sheet metal panels 112A-C together. This connection is similar to the connection illustrated in FIG. 23, except the sheet metal panels 112A-C do not include the side walls 138. Instead, the sheet metal panels 112A-C just overlap and engage the faces (e.g., a front face or a rear face) of the infill studs 136. The two infill studs 136 engage each other (e.g., positioned back-to-back) and are connected together, such as by fasteners (e.g., screws) 141. Each sheet metal panel 112A-C is attached to their corresponding infill stud 136 via the fasteners 140 (e.g., screws).
[0073] FIG. 25 illustrates another way of connecting the sheet metal panels 112A-C together. This connection is similar to the connection illustrated in FIG. 24, except that welds 142 (e.g., plug welds) are used to attach the sheet metal panels 112A-C to the infill studs 136.
[0074] Having described the disclosure in detail, it will be apparent that modifications and variations are possible without departing from the scope of the disclosure defined in the appended claims.
[0075] When introducing elements of the present disclosure or the preferred embodiments(s) thereof, the articles a, an, the and said are intended to mean that there are one or more of the elements. The terms comprising, including and having are intended to be inclusive and mean that there may be additional elements other than the listed elements.
[0076] In view of the above, it will be seen that the several objects of the disclosure are achieved and other advantageous results attained.
[0077] As various changes could be made in the above products without departing from the scope of the disclosure, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
