Patent Publication Number: US-8117788-B1

Title: Energy dissipating assembly for frame walls

Description:
RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 10/891,421, filed Jul. 13, 2004, now abandoned entitled “ENERGY DISSIPATING ASSEMBLY FOR FRAME WALLS” which is a continuation-in-part of U.S. patent application Ser. No. 09/932,181, filed on Aug. 17, 2001, now U.S. Pat. No. 6,761,001 entitled “A-FRAME SHEAR ASSEMBLY FOR WALLS,” which are hereby incorporated by reference in their entirety. This application also claims the benefit of U.S. Provisional Application No. 60/226,354, filed on Aug. 18, 2000, entitled “A-FRAME SHEAR ASSEMBLY FOR WALLS.” 
    
    
     BACKGROUND 
     1. Field 
     The present teachings relates to the construction industry and, in particular, concerns systems and methods for providing improving lateral strengthening and performance of wall structures using a shear assembly with energy-dissipating attachment members. 
     2. Description of the Related Art 
     Low-rise, commercial, institutional and residential (single and multi-family) buildings comprise the majority of buildings in the United States. Within this group of buildings, by far the most prevalent type of structure is the light framed structure, specifically wood or cold-formed/light-gauge steel framing. In the typical light framed building structure, as in any other building structure, the basic structural design goals is to ensure the safe performance of the building under anticipated loading conditions. Safe performance may include, but is not limited to, one or more of the following performance objectives: operational/immediate occupancy performance, life safety performance and collapse prevention performance (FEMA-273 “ NEHRP Guidelines for the Seismic Rehabilitation of Buildings,”  1997). 
     The loads to be considered in design vary in the degree by which they can be reasonably (in a probabilistic sense) defined. Fundamentally though, there are two types of load to consider in design: gravity and lateral loads. Gravity loads, as the name implies, act vertically and they have one characteristic that makes them more deterministic than lateral loads—they can be controlled to some extent. Lateral loads (for example those induced by earthquakes and hurricane/tornado winds) are unpredictable in both occurrence and magnitude. In design for lateral load, the conventional philosophy has been to provide a lateral load resisting structural system that is strong enough to resist the maximum expected design event. In earthquake resistant design, this philosophy is further augmented by the additional requirement for inelastic deformation capability (ductility) of the lateral load resisting system. Inherent in this ductility requirement is the understanding that under the maximum design event, a building will undergo some amount of damage associated with the design performance objectives stated above. 
     In conventional light framed building construction, gravity and lateral load resistance is achieved essentially by a stick frame (studs, joists, rafter and trusses) for the gravity loads and sheathing attached to the stick frame for lateral loads. Loads are typically generated at different levels within the building and must be carried to the foundation via the combined action of the stick frame and the attached sheathing. This combined action implies that some elements of the gravity and lateral load systems will be common. As a result, failure of any one of these common elements under one loading condition (say lateral) can compromise the integrity of the entire system under the other condition. 
     Sheathed stick-framed walls that are designed to resist lateral loads are commonly referred to in the literature as shear walls or vertical diaphragms. The details of how a shear wall resists lateral load are quite complex. Generally though, the basic mechanism of resistance is achieved by a transfer of load from the point where they are generated into the frame, from the frame into the sheathing, from the sheathing back into the frame and from the frame into the foundation. Because of this load path, each component in the load path needs to have capacity of transferring the full load for a shear wall to work as expected. In other words, the performance of the shear wall is controlled by its weakest link. In earthquake resistant design, performance is attained by having the capacity to transfer loads at the foundation be higher than the capacity of the sheathing to frame attachment. 
     The sheathing materials commonly used in light frame shear wall construction typically include plywood, oriented strand board, fiberboard, gypsum wallboard/sheathing board, siding and sheet steel. The sheathing is typically attached to the frame with nails, staples or screws. In some cases, as may be the case with light gauge steel framing, sheet steel may be attached to the frame by clinching, welding or an adhesive. Additionally, in cold-formed steel construction lateral resistance may also be accomplished with flat-strap x-bracing. These generic systems, which are typically included in building codes, are not the only means of providing lateral resistance. In fact, other prefabricated systems are available for use as braced wall components. The primary benefits of these systems are improved performance due to the quality control associated with fabrication of the component and ease of installation in the field. 
     The aforementioned prefabricated systems, though more advanced than shear and x-braced walls, provide a response similar to that of the conventional field-built shear wall. That is, to develop a certain level of lateral resistance under the design event, these systems must undergo significant inelastic deformation (damage) which in turn results in damage to the contents and other non-structural components of the building. Furthermore, conventional shear walls and other prefabricated panel systems used in light framed buildings, may have to be comparatively large or strong to withstand the magnitude of lateral loads and/or deformations that are generated in design events or as limited by building codes. For example, most building codes limit the inelastic story drift or lateral displacement to between 2 inches and 2.5 inches for an 8-foot wall height in all types of buildings. To meet this limitation, the braced wall (shear wall, x-bracing or prefabricated system) must generally be ductile (ability to deform), strong and stiff. As the stiffness and strength of bracing components increase, the demands placed on other components of the structure also increases, thereby requiring larger members. It can be appreciated that multi-story buildings will be more susceptible to larger lateral forces/deformations often necessitating even larger lateral bracing structures. Increased spatial requirements for the lateral bracing system exacerbates the problem of a limited amount of space in walls of smaller lengths. 
     Hence, there is a need for a lateral bracing system that is easy to install, is comparatively small in size so that it can be readily installed in walls having short lengths, has the ability to dissipate energy without significant damage to the structures (and its components), has the ability to reduce the magnitude of deformations and forces induced in the building, improves life-safety of occupants and protects building functionality. To this end, there is a need for a prefabricated internal shear assembly with a mechanical lateral motion energy dissipating device. 
     SUMMARY 
     The foregoing needs are addressed by one aspect of the present teachings relating to a system for reducing the effects of shear forces on a building structure. The system includes a wall comprising a plurality of vertical studs. The wall includes an upper portion and a lower portion and the upper portion of the wall is adjacent the upper portion of the building and the lower portion of the wall is adjacent a foundation of the building. The system further includes a shear assembly that fits within a space defined by two adjacent studs positioned laterally along the wall, the upper portion of the wall, and the lower portion of the wall, such that the shear assembly couples the upper portion of the wall to the foundation. The shear assembly includes a deformable coupling assembly having an upper end and a lower end such that a relative lateral displacement of the upper and lower ends causes a restorable deformation followed by a non-restorable deformation of the deformable coupling assembly. The upper end attaches to the upper portion of the wall in a substantially rigid manner. The shear assembly further includes an interconnecting assembly that interconnects the lower end of the deformable coupling assembly to the foundation in a substantially rigid manner such that the deformable coupling assembly couples the upper portion of the wall to the foundation so as to allow energy dissipation by restorable and non-restorable deformation of the deformable coupling assembly in response to a lateral shear force applied to the upper portion of the wall. 
     The deformable coupling assembly being positioned near the upper portion of the wall and the interconnecting assembly being attached to the foundation in a substantially rigid manner provides a relatively short moment arm for the shear force applied to the upper portion of the wall so that the shear force is countered by the deformable coupling assembly before being transmitted to the foundation. In one embodiment, the deformable coupling assembly includes a plurality of corrugations having a plurality of vertical plates joined by alternating upper and lower joining plates. The upper joining plates and lower joining plates respectively define the upper and lower ends of the deformable coupling assembly. 
     In one embodiment, the deformable coupling assembly includes a plurality of plates extending in a direction having a vertical component joined to the upper portion of the wall at a plurality of locations and to the interconnecting assembly at a plurality of locations such that the shear force applied to the upper portion of the wall is transmitted to the plurality of plates in a substantially direct manner. In one embodiment, the plurality of plates are formed by a corrugated member having alternating upper and lower joining plates that join a plurality of vertical plates. The upper joining plates and lower joining plates respectively define plurality of joining locations at the upper and lower ends of the deformable coupling assembly. 
     In one embodiment, the vertical plates act as leaf springs when the lateral displacement is restorable. In one embodiment, the non-restorable deformation of the deformable coupling assembly includes non-restorable bending of the vertical plates. In one embodiment, the non-restorable deformation of the deformable coupling assembly includes non-restorable folding or unfolding of corners defined by the vertical plates and the upper and lower joining plates. 
     In one embodiment, the system further includes a side coupling that deformably couples one of the studs to at least one of the upper or lower ends of the deformable coupling assembly. The side coupling provides additional energy dissipation during a displacement of the upper portion of the stud relative to the foundation. 
     In one embodiment, the corrugated deformable coupling assembly is configured so as to allow relatively easy installation and replacement. The corrugated deformable coupling assembly is formed from a strip of ductile metal so as to facilitate relatively easy fabrication. Such corrugated assembly dissipates energy by a combination of shear, bending, and tension of the plates. 
     In one embodiment, the corrugated deformable coupling assembly further includes a filler material interposed between the vertical plates so as to adjust the effects of the shear force. The filler material can be a material such as rubber or RUMBER. 
     In one embodiment, the wall includes a light metal frame. In one embodiment, the wall includes a wood frame. The deformable coupling assembly being able to deform in restorable and non-restorable deformation manners allows for greater flexibility in the design of energy dissipating characteristics of the coupling between the upper portion of the wall and the foundation. 
     In one embodiment, the interconnecting assembly includes an A-frame structure. In one embodiment, the interconnecting assembly includes a panel. In one embodiment, the interconnecting assembly includes a braced frame. 
     In one embodiment, the deformable coupling assembly in response to a reversed cyclic shear force deforms during each displacement of the top portion of the wall relative to the foundation, thereby increasing the energy dissipation of the reversed cyclic shear force. In one embodiment, the deformation of the deformable coupling assembly has a substantially hysteretic behavior resulting in larger reductions in earthquake effects, including forces and energy, that are imposed on light frame structures by a seismic event. 
     Another aspect of the present teachings relates to a system for reducing the effects of shear forces on a building structure. The system includes a wall comprising a plurality of vertical studs. The wall includes an upper portion and a lower portion, and the upper portion of the wall is adjacent the upper portion of the building and the lower portion of the wall is adjacent a foundation of the building. The system further includes a shear assembly that fits within a space defined by two adjacent studs positioned laterally along the wall, the upper portion of the wall, and the lower portion of the wall, such that the shear assembly couples the upper portion of the wall to the foundation. The shear assembly includes a deformable coupling assembly having a plurality of deformable members that extend along a direction having a vertical component. The shear assembly further includes an interconnecting assembly that interconnects the lower end of the deformable coupling assembly to the foundation in a substantially rigid manner. The plurality of deformable members are attached to the upper portion of the wall at a plurality of upper attachment locations in a substantially rigid manner. The plurality of deformable members are attached to the interconnecting assembly at a plurality of lower attachment locations in a substantially rigid manner, so that a shear force acting on the upper portion of the wall is transmitted substantially directly to the plurality of deformable members. 
     In one embodiment, the plurality of deformable members include a plurality of plates. In one embodiment, the plurality of plates are formed by a corrugated member having alternating upper and lower joining plates that join a plurality of vertical plates. The upper joining plates and lower joining plates respectively define plurality of joining locations at the upper and lower ends of the deformable coupling assembly. 
     In one embodiment, the vertical plates act as leaf springs when the lateral displacement is restorable. In one embodiment, the non-restorable deformation of the deformable members includes non-restorable bending of the vertical plates. In one embodiment, the non-restorable deformation of the deformable members includes non-restorable folding or unfolding of corners defined by the vertical plates and the upper and lower joining plates. 
     In one embodiment, the system further includes a side coupling that deformably couples one of the studs to at least one of the upper or lower ends of the deformable coupling assembly. The side coupling provides additional energy dissipation during a displacement of the upper portion of the stud relative to the foundation. 
     In one embodiment, the corrugated deformable coupling assembly is configured so as to allow relatively easy installation and replacement. The corrugated deformable coupling assembly is formed from a strip of ductile metal so as to facilitate relatively easy fabrication. Such corrugated assembly dissipates energy by a combination of shear, bending, and tension of the plates. 
     In one embodiment, the corrugated deformable coupling assembly further includes a filler material interposed between the vertical plates so as to adjust the effects of the shear force. The filler material can be a material such as rubber or RUMBER. 
     In one embodiment, the wall includes a light metal frame. In one embodiment, the wall includes a wood frame. The deformable coupling assembly being able to deform in restorable and non-restorable deformation manners allows for greater flexibility in the design of energy dissipating characteristics of the coupling between the upper portion of the wall and the foundation. 
     In one embodiment, the interconnecting assembly includes an A-frame structure. In one embodiment, the interconnecting assembly includes a panel. In one embodiment, the interconnecting assembly includes a braced frame. 
     In one embodiment, the deformable coupling assembly in response to a reversed cyclic shear force deforms during each displacement of the top portion of the wall relative to the foundation, thereby increasing the energy dissipation of the reversed cyclic shear force. In one embodiment, the deformation of the deformable coupling assembly has a substantially hysteretic behavior resulting in larger reductions in earthquake effects, including forces and energy, that are imposed on light frame structures by a seismic event. 
     Yet another aspect of the present teachings relates to a coupling assembly for a shear assembly. The coupling assembly is interposed between an upper portion of the wall and an interconnecting assembly. The interconnecting assembly is substantially rigidly mounted to a foundation and includes a top mounting member. The coupling assembly includes a plurality of deformable members having a first end and a second end. The plurality of deformable members extend along a direction having a vertical component. The coupling assembly further includes a plurality of first attachments that substantially firmly attach the plurality of deformable members to the upper portion of the wall. The coupling assembly further includes a plurality of second attachments that substantially firmly attach the plurality of deformable members to the top mounting member. A force that causes a relative displacement of the upper portion of the wall and the foundation is transmitted to the plurality of deformable members in a substantially direct manner via the plurality of first or second attachments so as to cause the plurality of deformable members to undergo a non-restorative deformation for a substantial portion of the relative displacement so as to dissipate the force. 
     In one embodiment, the deformable members includes a plurality of plates extending in a direction having a vertical component interposed between the first and second attachments. In one embodiment, the plurality of plates are part of a corrugated strip having alternating upper and lower joining sections such that the first attachments form attachment of the upper joining sections to the upper portion of the wall and the second attachments form attachment of the lower joining section to the top mounting member of the interconnecting assembly. The corrugated strip can be formed from a strip of ductile metal so as to facilitate relatively easy fabrication, installation, and replacement. The corrugated deformable coupling assembly dissipates energy by a combination of shear, bending, and tension of the plates. 
     In one embodiment, the coupling assembly further includes a filler material interposed between the plates so as to adjust the effects of the force on the coupling assembly. The filler material can be materials such as rubber or RUMBER. 
     In one embodiment, the plurality of deformable members respond to a reversed cyclic shear force at the top portion of the wall by deforming during each displacement of the top portion of the wall relative to the foundation, thereby increasing the energy dissipation of the reversed cyclic shear force. In one embodiment, the deformation of the deformable members has a generally substantially hysteretic behavior resulting in larger reductions in earthquake effects, including forces and energy, that are imposed on light frame structures by a seismic event. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a block diagram of one embodiment of a shear assembly having a deformable energy-dissipating member that dissipates a shear force at a selected location that results in a relatively short moment arm associated with the shear force acting near the top of a frame wall; 
         FIG. 2  shows an example response of the energy-dissipating member when subjected to a shear force; 
         FIGS. 3A  and B show deformation of one embodiment of the energy-dissipating member when subjected to a shear force; 
         FIG. 4A  shows one embodiment of a shear assembly that is adapted for use in light metal frame structures; 
         FIG. 4B  shows one embodiment of the energy-dissipating member of the shear assembly of  FIG. 4A ; 
         FIG. 4C  shows one embodiment of a connecting piece that connects the energy dissipating member of  FIG. 4B  to the top portion of the light metal frame; 
         FIG. 4D  shows a cross-sectional view of the connecting piece of  FIG. 4C  attached to a top rail that forms the top portion of the light metal frame; 
         FIG. 4E  shows a cross-sectional view of how one embodiment of the energy dissipating member is attached to the connecting piece of  FIG. 4C ; 
         FIG. 4F  shows a cross-sectional view of how one embodiment of the energy-dissipating member is attached to an interconnecting member that interconnects the energy-dissipating member to a base of the shear assembly; 
         FIG. 4G  shows one embodiment of the base that connects the shear assembly to a foundation that supports the light metal frame; 
         FIG. 4H  show a top cross-sectional view of the base of  FIG. 4G ; 
         FIG. 4I  shows a side cross-sectional view of the base of  FIG. 4G ; 
         FIG. 5A  shows one embodiment of a shear assembly that is adapted for use in wood frame structures; 
         FIG. 5B  shows one embodiment of the energy-dissipating member of the shear assembly of  FIG. 5A ; 
         FIG. 5C  shows one embodiment of the base of the shear assembly of  FIG. 5A ; 
         FIGS. 6A  and B show deformation of the energy-dissipating member of the shear assembly of  FIG. 5A  when subjected to a shear force; 
         FIG. 7  shows one embodiment of the shear assembly having a panel-type interconnecting assembly; and 
         FIG. 8  shows one embodiment of the shear assembly having a braced frame. 
     
    
    
     These and other aspects, advantages, and novel features of the present teachings will become apparent upon reading the following detailed description and upon reference to the accompanying drawings. In the drawings, similar elements have similar reference numerals. 
     DETAILED DESCRIPTION OF THE SOME EMBODIMENTS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 09/932,181, filed on Aug. 17, 2001, entitled “A-FRAME SHEAR ASSEMBLY FOR WALLS,” which is hereby incorporated by reference in its entirety. 
     The present teachings relate to a deformable energy dissipating assembly that couples the top portion of a wall frame to the foundation.  FIG. 1  shows a block diagram of one embodiment of a shear assembly  2000  having a deformable energy dissipating assembly  2002 . As described below, the energy dissipating assembly  2002  can be attached to the top portion of a frame  2008  in different manners. The energy dissipating assembly  2002  can also be attached to an interconnecting assembly  2004  so that the interconnecting assembly  2004  couples the energy dissipating assembly  2002  to a foundation  2006 . 
     As described below in greater detail, the shear assembly  2000  can be implemented in light metal frame structures as well as wood frame structures. The shear assembly  2000  can be pre-fabricated so as to include its own rectangular shaped frame that is dimensioned to fit within one of the wall frame&#39;s rectangular area defined by the wall&#39;s top, bottom, and vertical sections. Alternatively, the shear assembly  2000  can be installed between the existing vertical sections (studs, for example) so that the existing top, bottom, and vertical sections define the frame for the shear assembly  2000 . 
     In one embodiment, the shear assembly  2000  is mounted substantially firmly to the foundation  2006 , and the energy dissipating assembly  2002  is located at the top end of the interconnecting assembly  2004 . Thus, an energy dissipating coupling between the assembly  2002  and the top portion of the frame  2008  is located from the foundation  2006  by a distance of approximately H. By providing a relatively rigid platform for the energy dissipating coupling with respect to the foundation, a force F (denoted by an arrow  2012 ) acting on the top portion of the frame  2008  is given a relatively short moment arm with respect to the lower portion of the frame. Consequently, the force F is countered by the energy dissipating coupling before it can have a long-moment-arm effect on the lower portion of the frame. 
       FIG. 1  also shows the force  2012  causing the top portion of the frame  2008  to be displaced by an amount ΔX relative to the foundation  2006 . The displaced frame is denoted by a dashed frame  2010 . The interconnecting assembly  2004  is shown to be generally stationary with respect to the foundation  2006 . In one embodiment, the energy dissipating assembly  2002  is mounted substantially firmly to the top of the interconnecting assembly  2004 . Thus, relative movement of the top of the frame  2008  with respect to the interconnecting assembly (and thus the foundation  2006 ) due to the force  2012  is “absorbed” by the energy dissipating assembly  2002 . 
       FIG. 2  now shows an example response  2020  of one embodiment of the energy dissipating assembly. An example curve  2022  shows how the relative displacement ΔX can occur within the assembly in response to the shear force. For comparison, an example curve  2024  (dotted curve) representative of a spring device is shown. In one assumes an ideal spring behavior for the spring device, the spring&#39;s restorative force is proportional to the spring displacement (compressed or stretched). Thus, the spring device&#39;s response to the shear force includes a generally linear portion  2026 . Once the spring&#39;s mechanical limit (indicated by 2028) is reached (for example, when unable to compress further), the spring&#39;s response changes substantially abruptly. Such a change and subsequent behavior is indicated by a relatively sharp drop-off in the displacement response to the shear force. That is, the spring is unable to accommodate the shear force beyond the mechanical limit, and the shear force beyond that limit is transferred to the frame. 
     The spring device can be configured by selecting the spring&#39;s stiffness (spring constant) and/or the amount the spring is allowed to compress or stretch. Thus, the response curve  2024  can be adjusted to some degree. However, the useful spring restorative response is still limited to a generally linear response. 
     In one embodiment of the energy dissipating assembly, its response curve  2022  can include a generally linear restorative portion  2030  and a non-restorative portion  2034 . As described below in greater detail, an energy dissipating element of the energy dissipating assembly can be configured so that for a first range of displacement (of one portion of the element with respect to another portion), the element can be restored to its original configuration in a spring-like manner. Beyond the first range of displacement, as indicated by a restorative limit  2032 , the element deforms for a second range of displacement until it reaches a deformation limit  2036 . Beyond the deformation limit  2036 , the shear force is transferred to the frame. 
     One can see that the energy dissipating assembly allows for more variations in the shear force response configuration. For example, the steepness and range of the restorative response can be selected as desired for a given application. Similarly, the range and the manner in which deformation occurs can be selected. Thus, it will be understood that the response curves  2022  and  2024  are examples for the purpose of description. The restorative portion  2030  of the curve  2022  may be less steep than that of the curve  2024 . Also, the restorative limit  2032  of the curve  2022  may occur at a greater displacement than the limit  2028  of the curve  2024   
     One way to provide the restorative and deformable response of the energy dissipating assembly is to couple the interconnecting assembly and the top of the frame with one or more plates. Each plate can act as a leaf spring in the restorative range, and can deform when displaced beyond the restorative limit. 
       FIGS. 3A  and B show one embodiment of an energy dissipating assembly  2044  having a plurality of plates  2046  that couple an interconnecting assembly  2048  to a top section  2052 . The top portions of the plates  2046  are fastened to the top section  2052 , and the bottom portions of the plates  2046  are fastened to the interconnecting assembly  2048  via a mounting member  2056 . The bottom of the interconnecting assembly  2048  is shown to be secured to the foundation  2006  via a bottom mounting assembly  2054 . Examples of bottom mounting assemblies are described below in greater detail. 
       FIGS. 3A  and B further show that interconnecting assembly  2048  and energy dissipating assembly  2044  fit inside two vertical sections  2050 . As previously described, the vertical sections  2050  can be part of the existing wall frame, or part of a pre-fabricated assembly (including the interconnecting assembly and the energy dissipating assembly) that fits in the existing wall frame. 
       FIG. 3A  shows an at-rest configuration  2040  of the section of the wall having the energy dissipating assembly  2044 . In one embodiment, the plates  2046  in such a configuration are in a generally vertical orientation. 
       FIG. 3B  shows a configuration  2042  of the section of the wall subjected to a shear force that causes the top section  2052  to be displaced by an amount ΔX relative to the foundation  2006 . The plates  2046  are shown to be deformed in response to the displacement. 
     As is generally known, each of the plates  2046  can act as a leaf spring. Thus, when subjected to a displacement within its restorative range, the plate can be restored to its vertical orientation when the shear force is removed. When the shear force continues the displacement beyond the restorative limit, the plate is deformed, thereby dissipating the energy associated with the shear force. 
     The deformation of the plate is depicted in a simplified manner as being angled in  FIG. 3B . It will be appreciated, however, that the deformation can cause the plate to bend. Furthermore, the energy dissipating deformation may also include deformation of connecting structures that connect the plate to the top section  2052  and the mounting member  2056 . For example, the example embodiment of the plates  2046  shown in  FIGS. 3A  and B form a corrugation so that the top grooves are fastened to the top section  2052  and the bottom grooves are fastened to the mounting member  2056 . When such a corrugation is subjected to a shear force, the resulting deformation can deform the bends at the top and bottom grooves as well. In one embodiment, such deformation of structures about the plate occurs after the displacement exceeds the restorative range of the plate. 
       FIGS. 4A-I  now show one embodiment of a shear assembly  2060  adapted for light metal frame structures. As shown in  FIG. 4A , the shear assembly  2060  includes an energy dissipating assembly  2062  that couples a top section  2072  to an interconnecting assembly  2066 . The energy dissipating assembly  2062  is attached to the interconnecting assembly  2066  in a substantially firm manner. The interconnecting assembly  2066  is attached to the foundation  2006  in a substantially firm manner via a base mounting assembly  2068 . Thus, the energy dissipating assembly  2062  couples the top section  2072  to the foundation  2006  in a restorable and deformable manner at a location that provides a relatively short moment arm to a shear force acting on the top section  2072 . 
     In one embodiment, the interconnecting assembly  2066  and the energy dissipating assembly  2062  are dimensioned to generally fit between two vertical sections  2070 . The vertical sections  2070  can be part of the existing light metal frame wall, or part of a pre-fabricated assembly. The thickness (dimension in and out of plane of  FIG. 4A ) of the interconnecting assembly  2066  and the energy dissipating assembly  2062  are also selected to allow flush mounting of flat panels to the vertical sections  2070 . 
     In the description herein, the interconnecting assembly is in the form of an A-frame. It will be appreciated, however, that other structures can couple the foundation to the energy dissipating assembly in a secure manner without departing from the spirit of the present teachings. 
     The example A-frame interconnecting assembly  2066  includes two legs  2080  arranged in an “A” configuration. As shown in  FIG. 4A , the shear assembly  2060  may further include a brace  2082  that braces the mid-portion of the two legs  2080 . In one embodiment, the brace  2082  is securely attached to the two vertical sections  2070 , and defines horizontal slots  2084  that permit horizontally slidable coupling of the legs  2080  to the brace  2082  (via bolts  2086 ). Thus, the brace  2082  inhibits buckling of the legs in a direction in and out of the plane of  FIG. 4A , and allows the vertical sections  2070  to be displaced in a generally horizontal manner with respect to the interconnecting assembly  2066 . 
       FIGS. 4B-F  show various views of parts associated with the energy dissipating assembly  2062 .  FIG. 4B  shows a close-up of the assembly  2026 , and how it is attached to the legs  2080  of the interconnecting assembly ( 2066  in  FIG. 4A ) and coupled to the top section  2072 . 
     In one embodiment, the coupling and energy dissipating function of the assembly  2062  is provided by a plurality of deformable plates  2104  joined at the top and bottom in an alternating manner so as to form a plurality of corrugations  2102 . Adjacent plates  2104  are joined at the top by a top joining plate  2106  that defines a mounting hole  2110 . The mounting holes allow attachment of the top joining plates  2106  to the top section  2072  in a manner described below. A bottom joining plate  2108  joins adjacent plates  2104  at the bottom so that bottom joining plates  2108  and top joining plates  2106  alternate in the corrugation pattern. The bottom joining plates  2108  define mounting holes  2112  that allow attachment of the bottom joining plates  2108  to the legs  2080  in a manner described below. 
     In one embodiment, the plurality of corrugations  2102  are attached to the top section  2072  in the following manner. An inverted-hat shaped channel  2120  that extends laterally parallel to the top section  2072  joins the top joining plates  2106  of corrugations  2102  to an inverted C-shaped top rail  2122  that forms the top section  2072 . The inverted-hat channel  2120  has a cross-sectional shape including a hat-top  2146  that joins two hat-sides  2140  so as to form a U-shape (with the hat-top being the bottom of the “U”). Hat-brims  2142  extend outward and are generally parallel to the hat-top  2146 . The hat-brims  2142  are dimensioned to fit within the top rail  2122 , and are attached to the inside inverted C-shaped top rail  2122 . In one embodiment, the attachment of the hat-brims  2142  to the top rail  2122  is achieved by a plurality of clinches  2124 , thereby firmly attaching the inverted-hat channel  2120  to the top section  2072 . 
     The hat-top section  2146  defines a plurality of mounting holes  2126  that substantially align with the holes  2110  when the hat-top section  2146  is positioned above the top joining plates  2106 . A fastener  2134  extends through the holes  2126  and  2110  so as to mount the top joining plates  2106  to the hat-top  2146  and thus to the top section  2072 . In one embodiment, the fastener  2134  is a bolt that is secured with a nut. In one embodiment, mounting plates  2130  and  2132  (not shown in  FIG. 4E , and having holes that match the holes  2126  and  2110 ) are positioned above and below the hat-top section  2146  to act as strengthen the mounting of the top joining plates  2106  to the hat-top  2146 . 
     In one embodiment, the plurality of corrugations  2102  are attached to the legs  2080  of the interconnecting assembly  2066  in the following manner. As shown in a side sectional view in  FIG. 4F , each leg  2080  of the interconnecting assembly is formed by two hollow posts having a rectangular cross-sectional shape (each hollow post is also denoted as  2080 ). Thus in one embodiment, the interconnecting assembly includes two layers of “A” shaped legs. Interposed between the two layers of legs is a top cross member  2090  that extends horizontally and joins the tops of the legs. 
     In one embodiment, the top cross member  2090  is a hollow post having a rectangular cross-sectional shape and cut in length to accommodate the attachment of the corrugations  2102 . As shown in  FIGS. 4B  and F, side walls of the top cross member  2090  defines mounting holes  2170  that matches with mounting holes  2172  defined near the top of the legs  2080 . The holes  2170  and  2172  lined up can receive mounting bolts  2092  that secure the tops of the legs  2080  in a substantially rigid manner. As shown in  FIG. 4F , holes defined on the outer sides of the legs and in-line with the holes  2170  and  2172  can be made larger to allow bolt heads and nuts to pass through. Such recessed mounting of the mounting allows bolts  2092  to be secured without protruding beyond the outer sides of the legs. 
     As shown in  FIGS. 4B  and F, the top cross member  2090  that firmly secures the tops of the legs  2080  is positioned so that its top side is underneath the bottom joining plates  2108  of the corrugations  2102 . The top side (of the top cross member  2090 ) defines a plurality of mounting holes  2096  that align with the holes  2112  on the bottom joining plates  2108 . The bottom side (of the top cross member  2090 ) also defines a plurality of mounting holes  2094  that are in-line with the holes  2112  and  2096 . A fastener such as a bolt  2098  extends through each set of in-line mounting holes  2112 ,  2096 , and  2094 , thereby securing the corresponding bottom joining plate  2108  to the top cross member  2090  and thus to the legs  2080 . 
     As further shown in  FIGS. 4B  and F, the energy dissipating assembly  2062  may also include additional couplings between the legs  2080  and the top portions of the vertical sections  2070 . Such couplings can provide flexibility in the design of the operating characteristics of the energy dissipating assembly and the manner in which the assembly is installed. 
     In one embodiment, the additional couplings include a side coupling  2050  that couples the legs  2080  to the top portion of the vertical sections  2070 . In one embodiment, each vertical section  2070  is formed by two C-channels joined back-to-back (as shown in the cross-sectional view in  FIG. 4H , and also referred to as web-to-web). The side coupling  2050  includes a bottom plate  2152  that extends laterally outward from the bottom of the outer-most deformable plates  2104  into the “C” of the inner C-channel (of the vertical section  2070 ). The bottom plate  2152  then bends downward to form a side plate  2154 . The side plate defines a mounting hole  2156  that allows a fastener such as a bolt  2158  to secure the side plate to the backs (webs) of the “C”s of the vertical section  2070 . 
     In one embodiment, the additional couplings further include a lower coupling  2164  that couples the vertical section/top section “side” to the bottom of the cross member  2090 . In one embodiment, the lower coupling  2164  is connected to the side coupling  2150  by a lower lateral plate that is a substantial mirror image (about the horizontal line that extends through the middle of the cross member  2090 ) of the bottom plate  2152 . The lower lateral plate is connected to a structure that is a mirror image to the two outermost deformable plates  2104  and the corresponding outermost bottom joining plate  2108 . The mirror image of the outermost bottom joining plate  2108  is denoted as a mounting plate  2160  that defines a mounting hole  2162  for receiving the outermost fastener  2098 . 
     In one embodiment, the corrugations  2102 , side couplings  2150 , and lower coupling  2164  are formed from a single piece of an approximately 50 ksi steel of 10 gauge or thicker. As shown in  FIGS. 4E  and F, one embodiment of the single-piece coupling member can be formed from a strip of such a metal, where the strip has a width similar to the thickness of the cross member  2090 . In one embodiment, the cross-member  2090  has a cross-sectional dimension of approximately 1.5″×3.5″, and thus the width of the strip as shown has a width of approximately 1.5″. It will be appreciated that the strip can have other widths and provide the energy dissipating function. One can see that the deformation property of the strip can be adjusted by adjusting the width of the strip. 
     Preferably, the width of the strip is no larger than the combined thickness of the two layers of the legs  2080  with the cross member  2090  sandwiched therebetween ( FIG. 4F ) so that the strip does not interfere with flush fitting of the shear assembly in a wall frame. In the embodiment where the vertical sections  2070  are back-to-back (web-to-web) C-channels, the width of the strip is preferably selected to allow the side coupling to fit within the lips of the inward facing C-channels. 
     Aside from the material, thickness, and width of the deformable plates  2104 , there are numerous ways of adjusting the deformation and other mechanical properties of the coupling. For example, the height of the deformable plates  2104  can be adjusted. The number of deformable plates  2104  (number of corrugations  2102 ) can be adjusted as well. Thus, one can see that the energy dissipating coupling can be configured in numerous ways to suit different structural design requirements and applications. Some design considerations may include, but are not limited to, type of structure, vertical load bearing capability of the coupling at rest, and the coupling&#39;s restorative and deforming response to a shear force. 
       FIGS. 4G-I  now show details of one embodiment of the base mounting assembly  2068  that mounts the interconnecting assembly to the foundation in a substantially rigid manner.  FIG. 4G  is a front sectional view,  FIG. 4H  is a top sectional view, and  FIG. 4I  is a side sectional view. As previously described herein, the substantially rigid mounting of the interconnecting assembly to the foundation provides a relatively short moment arm for the shear force acting on the top portion of the wall frame. As such, the shear force is countered by the energy dissipating coupling before the shear force (if any left over) is transmitted to the base mounting assembly with a longer moment arm. 
     For the shear assembly adapted for light metal frame structure ( FIGS. 4A-I ), one embodiment of the base mounting assembly  2068  anchors the interconnecting assembly to the foundation in the following manner. As described above in reference to  FIG. 4F , one embodiment of the interconnecting assembly includes two layers of A-shaped legs  2080 . 
     For such an arrangement, the bottom portions of the legs  2080  are secured to each other via a bottom cross member  2182 . In one embodiment, the bottom cross member  2182  is a longer version of the top cross member  2090 , and has a length to fit between inner C-channels  2212  ( FIG. 4H ) of the vertical section  2070 . As shown in  FIG. 4I , the sides of the bottom cross member  2182  define mounting holes  2192  that align with mounting holes  2194  defined at the bottom portions of the legs  2080 . The aligned holes  2192  and  2194  allow the legs  2080  to be secured to the bottom cross member  2182  via fasteners such as bolts  2192 . Similar to the top cross member, the outer sides of the legs  2080  define enlarged holes aligned with the holes  2192  and  2194  so as to allow passage and recessed positioning of bolt heads or nuts. Assembled in the foregoing manner, the legs  2080  secured by top and bottom cross members  2090  and  2182  form a substantially rigid interconnecting structure. 
     In one embodiment, the top side of the bottom cross member  2182  defines a plurality of mounting holes  2190 , and the bottom side defines a plurality of mounting holes  2198  that generally align vertically with the holes  2190 . As shown in  FIG. 4G , the mounting holes  2190  and  2198  receive anchors such as bolts  2202  and  2204  that protrude from the foundation  2006 . In one embodiment, the outer set of anchor bolts  2202  resist the uplifting forces placed on the interconnecting assembly, and the inner set of anchor bolts  2204  resist lateral movement of the interconnecting assembly. 
     In one embodiment, bottom ends of the vertical sections  2070  and legs  2080  are positioned within a space defined by a bottom rail  2184  that sits on the surface  2180  of the foundation  2006 . In one embodiment, the base mounting assembly  2068  can further include compression plates  2186  interposed between the ends of the legs  2080  and the bottom rail  2184 . Such plates  2186  can distribute downward forces of the legs placed on the surface  2180  of the foundation  2006 . 
     In one embodiment, various components of the shear assembly described above in reference to  FIGS. 4A-I  have the following dimensions and properties. The inverted-hat channel  2120  is formed from an approximately 33 ksi or greater steel of 18 gauge or thicker. The top and bottom cross members  2090  and  2182  are steel hollow posts (tubes) having an outer cross-sectional dimension of approximately 3.5″×1.5″ and the wall thickness of approximately 16 gauge or thicker. The length of the top cross member  2090  can be selected to accommodate the top ends of the legs  2080 , and also to limit the lateral displacement (example in  FIG. 3B ) of the top portion of the vertical sections  2070 . The length of the bottom cross member  2182  is selected to accommodate the bottom ends of the legs  2080 , and to fit between the vertical sections  2070 . Each of the legs  2080  is a hollow steel post (tube) having an outer cross-sectional overall thickness of approximately 1″ and the wall thickness of approximately 16 gauge or thicker. The length of each leg  2080  can be selected to allow the desired “A” configuration and to accommodate the energy dissipating assembly at the top. 
       FIGS. 5A-C  now show one embodiment of a shear assembly  2300  adapted for a wood stud frame structure. Similar to the shear assembly described above in reference to  FIGS. 4A-I , the shear assembly  2300  includes an energy dissipating assembly  2302  that couples an interconnecting assembly  2308  to a top section  2304  of the frame structure. The interconnecting assembly  2308  is rigidly mounted to a foundation  2306  via a base mounting assembly  2310 . 
     As shown in  FIG. 5A , the energy dissipating assembly  2302 , interconnecting assembly  2308 , and the base mounting assembly  2310  are dimensioned to fit between two vertical sections  2312 . In one embodiment, the shear assembly  2300  may be pre-fabricated as a unit that includes the vertical sections  2312  and the top section  2304 . The shear assembly  2300  described in reference to  FIGS. 5A-C  is such a unit. It will be appreciated, however, that in other embodiments, the shear assembly  2300  having the energy dissipating assembly  2302 , interconnecting assembly  2308 , and the base mounting assembly  2310  can be installed between two existing adjacent studs of the frame structure without departing from the spirit of the present teachings. 
     In one embodiment, the shear assembly  2300  has an overall thickness (along the direction in and out of the page of  FIG. 5A ) that allows flush mounting of flat panels to the studs  2312 . In one embodiment, the shear assembly  2300  further includes a brace  2314  that braces the mid portion of the interconnecting assembly  2308  and allows a limited lateral movement of the studs  2312  with respect to the interconnecting assembly  2308  in a manner similar to that described above in reference to  FIG. 4A . 
     In one embodiment, the interconnecting assembly is in the form of an A-frame. It will be appreciated, however, that other structures can couple the foundation to the energy dissipating assembly in a secure manner without departing from the spirit of the present teachings. As shown in  FIG. 5A , the example A-frame interconnecting assembly  2308  includes two legs  2320  arranged in an “A” configuration. 
       FIG. 5B  shows a detailed view of the top portion of the shear assembly  2300 . In one embodiment, a frame of the pre-fabricated shear assembly includes a top plate  2304  that joins the top ends of the vertical (stud) sections  2312 . In one embodiment, the top plate  2304  is formed by two 2×4 nominal wood members having a length approximately equal to the distance between the outer sides of the two adjacent vertical (stud) sections  2312 . Each of the vertical (stud) sections  2312  is formed by two 2×4 nominal wood members. 
     In one embodiment, an outer strap  2370  having an inverted “U” shape attaches the outer sides of the top of the vertical stud sections  2312  to the top and ends of the top plate  2304 . Each of the three sections of the inverted-U shaped outer strap  2370  has a width that is similar to the thickness (3.5″ in one embodiment that uses the 2×4 nominal wood members) of the top plate  2304  and the vertical sections  2312 . Each of the three sections defines a plurality of fastening holes that allow passage of a plurality of fasteners  2374  that secure the outer strap  2370  to the top plate  2304  and the top ends of the vertical stud sections  2312 . In the embodiment where two 2×4 nominal wood members are used for the top plate and the vertical stud sections, the fasteners  2374  are preferably long enough to extend into the lower/inner wood members, so that the fasteners  2374  also secure the two wood members. In one embodiment, the fasteners  2374  are nails, but it will be understood that any other fasteners can achieve similar results. In one embodiment, the outer strap may be thin enough that fastening holes may not need to be pre-formed. Nails or similar fasteners may be driven through the thin sections and into the top plate  2304  and the vertical sections  2312 . 
     In one embodiment, an inner strap  2360  having an inverted “U” shape attaches the inner sides of the top of the vertical stud sections  2312  to the bottom of the top plate  2304 . In one embodiment, the inner strap  2360  is secured in a manner similar to that of the outer strap  2370 . 
     As shown in  FIG. 5B , the coupling and energy dissipating function of one embodiment of the assembly  2302  is provided by a plurality of deformable plates  2342  joined at the top and bottom in an alternating manner so as to form a plurality of corrugations  2340 . Adjacent plates  2342  are joined at the top by a top joining plate  2344  that defines a mounting hole  2352 . The mounting holes allow attachment of the top joining plates  2344  to the top plate  2304  in a manner described below. A bottom joining plate  2346  joins adjacent plates  2342  at the bottom so that bottom joining plates  2346  and top joining plates  2344  alternate in the corrugation pattern. The bottom joining plates  2346  define mounting holes  2350  that allow attachment of the bottom joining plates  2346  to the legs  2320  in a manner described below. 
     In one embodiment, the plurality of corrugations  2340  are attached to the top plate  2304  in the following manner. The horizontal sections of the outer and inner straps  2370 ,  2360  define mounting holes  2372 ,  2362  that align with the mounting holes  2352  on the top joining plates  2344 . The top plate  2304  defines a plurality of holes aligned with the mounting holes  2372  and  2362 , so that a plurality of fasteners such as bolts  2356  can pass through the aligned holes  2372 ,  2362 , and  2352  and secure the top joining plates  2344  to the top plate  2304 . 
     In one embodiment, such as that shown in  FIG. 5B , the plurality of corrugations  2340  are attached to the legs  2320  via a top cross member  2330  in a manner generally similar to that of the attachment described above in reference to  FIGS. 4B  and F. 
     In one embodiment, the energy dissipating assembly  2302  includes a side coupling  2410  that couples the top cross member  2330  to each of the vertical sections  2312 . 
     In one embodiment shown in  FIG. 5B , the side coupling  2410  includes an inner angled plate  2396  that extends upward at and outward from the outermost bottom joining plate  2346 . The upper end portion of the inner angled plate  2396  is coupled to the upper end portion of an outer angled plate  2394  such that the inner and outer angled plates  2396  and  2394  form an inverted “V” shape. 
     Such an inverted V-shaped structure can be formed by bending of a single strip of metal. In one embodiment as shown in  FIG. 5B , the upper end portions of the inner and outer angled plates  2396  and  2394  have additional vertically extending sections that are capped and secured by a cap  2400  so as to form an inverted “Y” shaped structure  2404 . 
     As shown in  FIG. 5B , the outer angled plate&#39;s ( 2394 ) lower end portion is joined with a downward extending vertical plate  2380 . The vertical plate  2380  is positioned adjacent the inner side of the vertical section  2312 , and defines a mounting hole  2382  that allows a fastener such as a bolt  2334  to secure the vertical plate  2380  to the inner side of the vertical section  2312 . In one embodiment, a mounting plate  2384  (having a mounting hole) is interposed between the vertical plate  2380  and the fastening end (such as a nut) so that the fastening force of the nut is distributed. 
     In one embodiment, a lower Y-shaped structure  2402  similar to (but inverted with respect to) the upper Y-shaped structure  2404  is joined to the lower end of the vertical plate  2380 . Thus, the upper and lower Y-shaped structures  2404  and  2402  form a deformable bellow-like structure that couples the legs  2320  (via the top cross member  2330 ) to the inner sides of the vertical sections  2312 . When a shear force pushes the upper portion of the vertical section  2312  towards the legs  2320 , the bellow structure can collapse and dissipate at least some of the energy associated with the force. When a shear force causes the upper portion of the vertical section to move away from the legs  2320 , the bellow structure can stretch and dissipate at least some of the energy associated with the force. 
     In one embodiment, the caps  2400  (that couple the inner and outer angled plates  2396  and  2394 ) allow the corrugations  2340  and the side couplings  2410  on both sides to be formed as separate pieces and joined during assembly. In certain situations, such a feature may be desired over a single-piece coupling (such as that described above in reference to  FIG. 4B ). 
     In one embodiment, as shown in  FIG. 5B , spaces defined by the deformable plates  2342  can be filled with various materials having different mechanical properties. As an example, energy absorbing materials such as rubber or “RUMBER” (a lumber-like structure formed from recycled rubber) can be dimensioned to fit in the spaces as shown. Such filler materials can be used to obtain a desirable response of the energy dissipating assembly  2302  (or the assembly  2062  of  FIG. 4B , although not shown). 
     In one embodiment, the corrugations  2340  are formed from a metal strip having a thickness of approximately 10 gauge. The outer portions of the side couplings  2410  are formed from a metal strip having a thickness of approximately 10 gauge. 
       FIG. 5C  now shows various details of the base mounting assembly  2310 . 
     In one embodiment, the assembly  2310  secures the legs  2320  of the interconnecting structure to the foundation  2306  in a substantially rigid manner. 
     In one embodiment as shown in  FIGS. 5A-C , the shear assembly  2300  is a prefabricated unit. Thus, the bottom ends of the vertical sections  2312  are attached to a bottom plate  2460  by an outer strap  2450  in a manner similar to that described above in reference to the outer strap  2370  of  FIG. 5B . In one embodiment, the bottom plate  2460  is a 2×4 nominal wood member. 
     As further shown in  FIG. 5C , the legs  2320  are secured at the bottom by a bottom cross member  2430  in a manner similar to that described above in reference to  FIG. 4G . Similarly, the bottom cross member  2430  receives and secures to uplift-resisting anchor bolts  2440  and lateral-movement-resisting bolts  2442  in a manner similar to that described above in reference to  FIG. 4G . 
     In one embodiment, a tubular sleeve  2462  is embedded in the bottom plate  2460  at a location that allows the uplift-resisting anchor bolts  2440  to pass vertically therethrough. Such a sleeve can inhibit crushing damages to the bottom plate  2460 . 
     In one embodiment, compression plates  2466  are interposed between the tops of the sleeves  2462  and the bottom side of the cross member  2430 . Such compression plates can distribute the downward forces applied by the legs  2320  on the sleeves  2466  and areas around them. 
     In one embodiment, various components of the shear assembly described above in reference to  FIGS. 5A-C  have the following dimensions and properties. The corrugations  2340  are formed from a single metal strip having a thickness of approximately 10 gauge. 
       FIGS. 6A  and B show at-rest  2480  and displaced  2482  configurations of the shear assembly  2300  described above in reference to  FIGS. 5A-C . As shown in  FIG. 6B , a shear force F acting on the top plate  2304  causes the top plate  2304  and the upper portion of the vertical sections  2312  to be displaced laterally by an amount ΔX. When subjected to a displacing shear force F, the plurality of corrugations  2340  are depicted as being deformed. Furthermore, one ( 2500 ) of the side couplings  2410  collapses by deformation, and the other (2502) becomes stretched by deformation. The deformations of the corrugations and/or the side couplings can thus provide the energy dissipating function in response to the shear force. 
     As shown in  FIG. 6B  (and also in  FIG. 3B ), the deformation of the corrugations is depicted as bending of the corners above and below the deformable plates. It will be understood, however, that such deformation is just one of numerous possible modes of energy-dissipating deformation modes. For example, the deformable plate can act as a leaf spring for the initial phase of the displacement, and when the restorative limit is exceeded, the plate itself can bend in a deforming manner. As shown in  FIG. 6B , the folded corners above and below the plate can also deform by folding and unfolding. 
       FIG. 7  now shows an example of a shear assembly  2600  where an interconnecting assembly  2604  is not an A-frame type structure. In one embodiment, the interconnecting assembly  2604  is a panel. Such a panel can have a structure similar to those disclosed in the U.S. patent application Ser. No. 09/932,181, filed on Aug. 17, 2001, entitled “A-FRAME SHEAR ASSEMBLY FOR WALLS.” Also, the panel  2604  can be secured to the foundation  2606  in a similar manner. 
     In one embodiment, the panel  2604  is coupled to a top plate  2610  by a deformable energy dissipating assembly  2602  depicted as a plurality of corrugation. As seen from the description herein, the assembly  2602  can be configured and mounted to the panel  2604  and top plate  2610  in a variety of ways to provide the energy dissipating function. The assembly  2602  can also be configured to couple to the upper portion of vertical sections  2612 . 
       FIG. 8  now shows an example of another embodiment of a shear assembly  2700  where the interconnecting assembly includes a braced frame  2702 . In one embodiment, the braced frame  2702  includes a rectangular frame  2704  braced by a plurality of alternating diagonal brace members  2706 . As shown in  FIG. 8 , two adjacent diagonal brace members  2706  and a vertical section  2720  of the rectangular frame  2704  generally form a “K” shape. As an example, the diagonal brace members  2706   a  and  2706   b  join at the vertical section  2720  to form the “K” shape. Another (reverse) “K” shape is formed by the diagonal brace members  2706   b  and  2706   c.    
     The number of diagonal brace members  2706  (and thus the number of “K”s) can vary depending on the design of the “K” brace frame. In one embodiment, the rectangular frame  2704  and the diagonal brace members  2706  are hollow metal tubes (e.g., hollow rectangular tubes), and the K-frame is formed by welding of such tubes. 
     In one embodiment, the K-brace frame  2702  is substantially rigidly attached to a cross member  2710  via a connecting piece  2708 . A deformable coupling assembly  2712  can be mounted to the cross member  2710  and also to a top section  2714  in a manner described herein so as to deformably couple the top section  2714  to the K-brace frame  2702 . In one embodiment, the K-brace frame  2702  is substantially rigidly attached to the foundation  2722  via a base mounting assembly  2716 . Thus, the K-brace frame  2702  provides a substantially rigid coupling between the deformable coupling assembly  2712  and the foundation  2722 . 
     From the foregoing description of the various embodiments of the deformable couplings, one can see that the energy dissipation can be achieved by some combination of shear, bending, and/or tension of the deformable component(s) of the coupling. Such modes of deformation counter the shear force that is applied nearby, so that the deformation of the coupling occurs substantially before, if any, the shear force is transmitted to the lower portion of the frame wall. 
     As seen in the description herein, the deformation of the various components of the coupling is facilitated providing attachment points relatively close to the deformable components. For example in the corrugation embodiment, the alternating top and bottom joining segments are attached respectively to the top section and the interconnecting assembly. While it is not a requirement to have every such joining segments attached, such attachments provide a more direct transfer of the shear force to the deformable component. 
     In the corrugation embodiments of the deformable coupling, the deformable “plates” extend in a direction having a component that is perpendicular to the lateral shear force. As previously described, materials and dimensions of such deformable plates can be selected to meet the desired design requirements for different building applications. 
     It will be appreciated that various embodiments of the deformable components of the coupling are described herein as deforming in one “direction” in response to the applied shear force. In some shear force situations, such as an earthquake, the shear force is not necessarily in one direction. Some combination of the earthquake-related force and the mechanical property of the building structure may cause the shear force to somewhat oscillate. In such situations, the deformable coupling of the present teachings can provide a desired response. A device that deforms in the foregoing manner generally does not produce a pinched hysteresis response to reversed cyclical forces, but instead produces substantially hysteretic behavior resulting in larger reductions in earthquake effects, including forces and energy, as can be imposed on light frame structures by a seismic event. That is, the reverse shear force (to the original shear force in a first direction) causes the deformed coupling to deform the other way. Such “second” deformation may not restore the general configuration of the coupling, the second deformation itself dissipates the energy associated with the reverse shear force. Such reversed cyclical forces can be reduced each time the shear force reverses direction. Again, each of these reversed cyclical shear forces are countered by the deforming coupling before being transferred to the lower portion of the frame wall. 
     As described herein, at least some of the various embodiments of the deformable couplings reduce damage to the wall frame by acting as a deformable sacrificial couplings. That is, once the coupling has performed its intended function, it becomes deformed so that subsequent use may not be desired. 
     The manner in which various embodiments of the deformable couplings are mounted allows the sacrificial couplings to be initially installed and subsequently replaced (if necessary) relatively easily. As an example, one embodiment of the coupling is shown in  FIG. 4B  and described above, where the plurality of mounting fasteners can facilitate an example replacement as follows, assuming that the top portion of the shear assembly becomes accessible (e.g., by have a portion of the panel removed). Nuts associated with the bolts  2134  can be removed from the bottom thereby freeing the coupling from the top portion of the frame, and the bolts can remain extending downward from within the inverted-hat channel  2120 . Nuts associated with bolts  2098  can be removed from the top of the cross member  2090 , and the bolts  2098  can be urged out downward, thereby freeing the coupling from the interconnecting assembly. The sides of the coupling can be freed from the vertical sections by removing the bolts  2158 . Once the coupling is freed from the top, bottom, and side engagements, it can be removed in a relatively easy manner. Because the coupling that is not attached to anything can be restorably deformed to some degree, installation of a new unit into the mounting position (e.g., into the C-channel) can be achieved in a relatively easy manner. The installation can be achieved in a generally reverse manner as the removal. Also, the coupling embodiment shown in  FIG. 5B  and described above can be removed and installed in a similar relatively easy manner. 
     From the description herein, one can see that the various deformable couplings are not only relatively easy to replace, but are relatively easy to manufacture. Because the deformable couplings can be formed from common ductile strips of metal, they can be stamped out and formed by bending. Various mounting holes can also be punched out from the strips in a relatively easy manner. 
     Although the above-disclosed embodiments have shown, described, and pointed out the fundamental novel features of the invention as applied to the above-disclosed embodiments, it should be understood that various omissions, substitutions, and changes in the form of the detail of the devices, systems, and/or methods shown may be made by those skilled in the art without departing from the scope of the invention. Consequently, the scope of the invention should not be limited to the foregoing description, but should be defined by the appended claims.