US20070062135A1

US20070062135A1 - Corrugated shear panel and anchor interconnect system

Info

Publication number: US20070062135A1
Application number: US11/429,658
Authority: US
Inventors: Lee Mueller
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-06-30
Filing date: 2006-05-04
Publication date: 2007-03-22

Abstract

A system for inhibiting unwanted movement between a building and an underlying foundation, the system including at least one shear panel assembly including corrugated portions and configured to resist bending and twisting distortion and at least one hold-down assembly configured to attach to the at least one shear panel assembly and to attach to at least one anchor member rigidly engaged with an underlying building foundation so as to resist uplift, downward movement, and lateral movement of the at least one attached shear panel assembly, the at least one hold-down assembly configured to provide a range of vertical attachment adjustment to accommodate a range of extended length of the at least one anchor member.

Description

RELATED APPLICATIONS

This application is a continuation in part of U.S. application Ser. No. 09/897,740 filed Jun. 29, 2001 and claims thereby the benefit of U.S. Provisional Application No. 60/215,290, filed on Jun. 30, 2000

BACKGROUND OF THE INVENTION

1. Field of the Invention
The invention relates to the construction industry and, in particular, concerns a method of providing lateral strengthening of wall structures using factory manufactured, field installed framed corrugated diaphragm shear panels.
2. Description of the Related Art
In light frame construction, walls are typically constructed using load bearing framing members made from wood or metal. Most often, a series of vertical studs, periodically spaced usually 16″ to 24″ on center, are secured at top and bottom with horizontal members called plates or tracks so as to form a wall frame. The resulting wall frame is capable of vertical load bearing. However, the rectangular geometry of the wall frame provides minimal strength when subjected to a combination of axial loading and lateral forces applied horizontally at the top or bottom of the frame wall. Such a combined force, as occasioned by seismic or high wind events, tends to cause a racking motion between the top and bottom of the wall, and may cause damage ranging from cracks in the wall's surface finish materials to complete structural failure of the wall resulting in a building collapse.
One typical method of laterally reinforcing light frame walls involves securing diaphragm sheet panels of plywood, oriented strand board (OSB), or light gauge sheet steel to the wall frame studs. While the conventional, two-dimensional, planar-sheet diaphragm shear panel construction does provide rigidity for the light frame walls and does provide resistance against shear forces, conventional field constructed shear panels do have some drawbacks both in terms of method-of-construction and systems performance.
The drawbacks relating to method-of-construction pertain to the inherent potential for poor quality control in any field constructed assembly, especially where the efficacy of a system is dependent upon the proper connection and attachment of a multitude of components. A prefabricated factory assembled shear panel of any variety has a better potential for quality control and overall system performance than a completely field constructed assembly.
The potential system performance drawback to field built sheet diaphragm shear panels relates to the issue of ductility in the wall system. Wood frame systems are generally regarded as being relatively ductile systems which means they do not usually fail in a brittle or catastrophic mode, but rather fail in a gradual manner where they eventually loose their ability to resist forces. However, post earthquake and post hurricane forensic investigations and cyclic testing of sheet diaphragm shear panels has revealed that it is not uncommon for wood sheathing attached to light frame construction to tear apart at the panel edges where fastened with nails or screws. It has also been found that wood sheet diaphragms, when rigidly secured with fasteners at panel boundaries, have a tendency to tear and shear apart in the middle of the sheet diaphragm. This behavior is characteristic of an absence of ductility in the diaphragm element itself. Improvement in the ductile capacity of shear resisting elements in light frame construction whether field constructed or factory assembled and field installed is therefore an improvement in technology which would be beneficial in the design, engineering, and construction industry.
With respect to improvements in the method-of-construction of shear resisting elements in light frame construction, several patents have been issued since 1998 which disclose methods of providing pre-assembled lateral wall reinforcement. One such prefabricated shear reinforcement system was disclosed in U.S. Pat. No. 5,706,626 to Mueller, wherein a shear panel comprises a steel frame that fits between at least two vertical studs and secures the top and bottom of the wall. The area within the frame is covered by a flat sheet metal diaphragm. The flat sheet metal attached on both of the opposite sides of the vertical and horizontal chord members provides substantial resistance to torsional and lateral buckling in the panel. This reinforcement method is especially beneficial on the compression side of the vertical chord members. Thus the perimeter frame of the panel is braced and reinforced by the sheet diaphragm making the shear panel resistant to lateral deformation. The extent to which the prefabricated shear panel is ductile, however, is a function of the rigidity of the fastened assembly of the various components.
In recent years since the 1994 Northridge, Calif. earthquake and the 1995 Kobe, Japan earthquake, the architectural and structural engineering community has become increasingly concerned with developing appropriate building design methodologies capable of reducing the degree of structural damage sustained in these natural events. Structural designers and building code writing organizations have come to recognize the benefits of lateral resisting elements and systems in building design which not only resist lateral motion, but which provide a measurable degree of ductility which can absorb and dissipate energy in the process of resisting lateral loads imposed on building structures.
Cyclic testing of both wood diaphragm shear panels and metal shear panels, including braced frame types, unitary body types, and sheet diaphragm types, has disclosed that an absence of ductility in a panel or frame generally results in a buckling failure mode on the compression side of either the vertical end edge or chord member.
From the foregoing, it will be appreciated that there is a need for improved methods of shear reinforcing a wall frame so as to provide for the structural integrity of buildings. There is a need for a shear panel that can be substantially prefabricated, and be field installed into a light frame wall in a simple manner with some additional degree of field installation adjustability. There is a need for a shear panel that provides substantial resistance to shear forces and uplifting forces acting on the wall. There is a need for a shear panel with a substantially strong, yet ductile diaphragm that does not require additional lateral braces for over structural integrity.

SUMMARY OF THE INVENTION

The aforementioned needs are satisfied by the shear panel for transferring force from an upper region of a building to anchors mounted within the foundation of the building. The shear panel comprising of a plurality of frame members are formed so that in cross section, the frame members include laterally displaced sections that are laterally displaced from the axis of extension of the frame member, such that laterally displaced sections provide strength to the chord member so as to resist lateral buckling of the frame member under compression. A diaphragm that is attached to the frame defined by the plurality of frame members so as to transfer uplift forces from one region of the shear panel frame to another. An anchor assembly, connected to the frame of the shear panel so as to interconnect the shear panel to anchors mounted within the foundation of a building.
In one embodiment, the panel further comprises a first chord member having a laterally displaced section laterally displaced in a first direction. A second chord member having a laterally displaced section laterally displaced in a second direction, opposite of the first direction. Wherein the first and second chord members are secured together so as to define the frame member.
In yet another embodiment, the first and second chord members comprise a first section that defines a first at least partially enclosed space and a second section that defines a second at least partially enclosed space. Wherein the first and second sections are interconnected at a first end of the first and second sections and wherein the first and second sections are configured so that the first and second at least partially enclosed spaces are elongate and the axis of elongation of the first and second partially enclosed spaces are approximately perpendicular to each other.
In yet another embodiment, wherein the first section of the first and second chord members are positioned such that the axis of elongation of the first at least partially enclosed space is substantially co-axial between the first and second chord members. Wherein the second partially enclosed space of the first and second chord members are displaced from each other with the axis of elongation of the second partially enclosed space of the first and second chord members being displaced, but substantially parallel to each other.
In yet another embodiment, the laterally displaced sections are positioned within the second section of the first and second chord members.
In another embodiment, further comprising a first and a second reinforcing J members that have elongate sections that are positioned adjacent the second section of the first and second chord members and hook sections that are positioned within the first partially enclosed space of the first and second chord members.
In another embodiment, the first and second reinforcing J members are clinch connected to the first and second chord members.
In one aspect, the shear panel for transferring force from an upper region of a building to anchors mounted within the foundation of the building, the shear panel comprising of a plurality of frame members defining the frame of the shear panel. A diaphragm member that is attached to the frame defined by the plurality of frame members so as to transfer uplift forces from one region o the shear panel frame to another. The diaphragm is contoured so as to define a plurality of lateral displacements out of the plane of the diaphragm member to thereby provide resistance to bending of the shear panel in a direction that is perpendicular to the plane of the diaphragm member. An anchor assembly, connected to the frame of the shear panel, so as to interconnect the shear panel to anchors mounted within the foundation of the building.
In yet another embodiment, the diaphragm member is corrugated so as to define the plurality of lateral displacements.
In another embodiment, the diaphragm member is corrugated so that the plurality of lateral displacements extends in a direction that is generally horizontal.
In another embodiment, the diaphragm member is corrugated so that the plurality of lateral displacements extends in a diagonal manner.
In yet another embodiment, the diaphragm member is comprised of a first and second corrugated member that are positioned and interconnected, so as to define a plurality of rectangular openings that have side walls extending in a direction laterally outward from the plane of the opening defined by the frame members.
In another embodiment, the first and second corrugated members are arranged so as to define a plurality of rectangular openings that extend generally horizontally across the openings defined by the frame member.
In another embodiment, the first and second corrugated members are contoured so that the plurality of rectangular members is separated by a plurality of interconnecting sections of the first and second corrugated members. These members are positioned immediately adjacent to each other and interconnected with each other.
In yet another embodiment, wherein the plurality of interconnecting sections is interconnected to each other via clinching.
In another embodiment, the diaphragm member comprises a plurality of diaphragm sections that are individually connected to the frame member, so as to be positioned throughout the opening defined by the frame member. Wherein the plurality of diaphragm sections are coupled to the frame so as to reduce the overall length of the diaphragm member to thereby reduce the tendency of the diaphragm member to be damaged as a result of transferring force to the anchor members.
In another embodiment, wherein the plurality of diaphragm sections comprise three independent sections of corrugated material that are mounted to the frame members.
In another aspect of the invention a shear panel assembly for transferring force from an upper portion of a building to a foundation. The assembly comprising of a plurality of frame members defining the frame of the shear panel. A diaphragm that is attached to the frame defined by the plurality of frame members so as to transfer uplift forces from one region of the shear panel frame to another. An anchor member embedded in the foundation having ends extending outward therefrom. An anchor attachment member comprised of a U-shaped strap that connects to the outer edges of the plurality of frame members to the anchor attachment member. Wherein the anchor attachment member defining holes that receive ends of an anchor member embedded in the foundation, wherein the openings are aligned with the frame members so that when the anchor attachment member is attached to the frame members, the frame members are substantially concentric with the ends of the anchor member.
In another embodiment, the attachment members define two vertical sections with a horizontal section interposed therebetween and wherein the openings are formed in the horizontal sections, and the vertical sections are attached to the outer edges of the vertical frame members defining the frame of the shear panel assembly.
In yet another embodiment, the horizontal section defines two recess that have the openings that receive the ends of the anchor member.
In another embodiment, the openings are configured to permit adjustment of the frame members in a direction that is perpendicular to the plane of the diaphragm member.
In yet another embodiment, further comprising slotted steel capture plates positioned within the two recesses that receive the ends of the anchor structure therethrough.
In another embodiment, wherein the anchor member is comprised of a U shaped member having a first and second end, and an interconnecting section wherein the interconnecting section is embedded on the foundation with the first and second ends extending outwardly therefrom so as to permit attachment to the anchor attachment member.
In one aspect of the invention, a shear panel assembly for transferring force from an upper portion of a building to a foundation. The assembly comprising of a shear panel having a first and second outer edges and a central portion interposed therebetween wherein the shear panel is attached to the upper portion of the wall. A hold-down assembly that interconnects the first and second outer edges to first anchor bolts positioned within the foundation such that the hold-down assembly resists uplift forces. An anchor assembly that interconnects the central portion of the shear panel to second anchor bolts positioned in the foundation so that the anchor assembly resists base shear forces inducing relative movement between the bottom of the shear panel and the foundation.
In one embodiment, wherein the hold-down assembly comprises a first and second attachment assembly wherein each of the first and second attachment assemblies comprises of a hold-down bolt sleeve which defines an opening that receives a hold-down bolt within the opening. Wherein the hold-down bolt sleeve is attached to the shear panel. An attachment plate that includes an opening wherein the attachment plate is positioned on the sleeve so as to allow the hold-down bolt to extend through the opening such that the end of the hold-down bolt can be coupled to the first anchor bolt so as to secure the hold-down bolt sleeve to the first anchor bolt.
In yet another embodiment, wherein the opening of the hold-down bolt sleeve is laterally extending so as to extend in a direction perpendicular to the plane of the shear panel so as to permit attachment between the first anchor bolts and the shear panel when the first anchor bolt is misaligned with the shear panel in a direction perpendicular to the plane of the shear panel.
In another embodiment, wherein the hold-down assembly further comprises an interconnection device that interconnects the hold-down bolt sleeve to the outer edge of the shear panel.
In yet another embodiment, the interconnection device comprises at least a pair of members attached to the hold-down bolt sleeve so as to define a space that receives the outer edge of the shear panel and at least one bolt that extends between the pair of members in the space so as to be interconnected to the shear panel.
In another embodiment, further comprising at least one reinforcing member mechanically coupled to the at least one bolt. Wherein the reinforcing member engages with the foundation so as to resist compressive forces being exerted on the hold-down assembly.
In another embodiment, wherein the reinforcing member extends in a direction parallel to the hold-down bolt and has a lip that engages with the foundation.
In yet another embodiment, the anchor assembly includes a base member that defines an opening such that the bottom edge of the shear panel can be positioned within the opening and secured thereto.
In another embodiment, wherein the base member includes at least one first opening that receives the first anchor bolt. Wherein the first opening extends in a direction perpendicular to the plane of the shear panel so as to accommodate misalignment between the shear panel and the first anchor bolt in a direction that is perpendicular to the plane of the shear panel.
In yet another embodiment, the base member defines at least one second opening that receives the second anchor bolt. Wherein the second opening extends in a direction perpendicular to the plane of the shear panel so as to accommodate misalignment between the shear panel and the second anchor bolt in a direction that is perpendicular to the plane of the shear panel.
In another embodiment, wherein the base member is sized to fit in a steel framing track of a lower portion of the wall.
In yet another embodiment, a shear panel assembly for transferring force from an upper portion of a building to a foundation, the assembly comprising of a shear panel defining a planar area, wherein a plurality of corrugations are formed in the planar area of the shear panel. An attachment assembly for attaching the shear panel to the upper portion of the wall. An anchor assembly that interconnects the shear panel to the foundation, wherein the plurality of corrugations provide ductility in the shear panel thereby allowing limited compression and expansion of the shear panel when under shear loading to reduce buckling of the shear panel during shear loading.
In another embodiment, wherein the planar area comprises a first side and a second side, wherein the corrugations comprise a ridge and a groove on the first and second sides of the planar area. The corrugation on the first side of the planar area is substantially symmetric to the corrugation on the second side about the plane of the planar area.
In yet another embodiment, wherein the groove on the first side of the planar area is engaged with the groove on the second side of the planar area.
In another embodiment, wherein the grooves on the first and second area are secured by a plurality of clinches.
In another embodiment, wherein the substantially symmetric ridges on the first and second sides of the planar area defines a cavity.
In yet another embodiment, wherein the cavity is a hexagonal shape in cross section.
In another embodiment, wherein the planar area comprises a first layer and a second layer. Wherein each of the first and second layers comprise a plurality of ridges and grooves. The first and second layers are secured together such that the ridges and grooves are substantially symmetric in cross section about the plane parallel to and between the first and second layers.
In yet another embodiment, wherein each of the first and second layers comprises segmented sections. Wherein the segmented sections are joined together to form the first and second layers.
In another embodiment, wherein the segmented sections are joined by gusset straps to form butt joints.
In another aspect of the invention, a shear panel assembly for transferring force from an upper portion of a building to a foundation. The assembly comprising of a shear panel having a first and a second outer edges and a central portion interposed therebetween wherein the shear panel is attached to the upper portion of the wall. An anchor assembly that comprises at least one anchor bolt having a first leg and a second leg extending out of the foundation with an interconnecting section interposed therebetween. Wherein the interconnection section is embedded in the foundation to provide greater resistance to uplift forces.
In another embodiment, wherein the anchor assembly comprises two separate anchor bolts. Wherein the first anchor bolt is adapted to resist uplift forces and the second anchor bolt is adapted to resist shear forces.
In yet another embodiment, each of the first and second anchor bolts is an U-shaped bolt.
In yet another aspect of the invention, a wall assembly interconnection an upper portion of a building to a foundation. The assembly comprising of a plurality of vertical studs distributed along the wall assembly. A shear panel positioned between two adjacent vertical studs at least one location. The panel has a first and second outer edges and a central portion interposed therebetween wherein the shear panel is attached to the foundation. An attachment assembly for attaching the shear panel to the upper portion of the wall assembly. The attachment assembly comprises a top track that has more than two vertical components in cross section. The additional vertical components provide the wall assembly with greater resistance to shear and uplift forces acting on the building.
In yet another embodiment, the cross section of the top track comprises a first section and a second section with an interconnecting section interposed therebetween. Wherein the first and second sections are substantially parallel, wherein the interconnection section comprises at least one bend such that the cross section of the top track in M-shaped when the first and second sections are positioned vertically.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates two adjoining wall frames with shear panels in one embodiment of the invention installed;
FIG. 2A is a side elevation view of the shear panel;
FIG. 2B is an end elevation view of the shear panel;
FIG. 2C is a plan sectional view of the shear panel;
FIG. 3A illustrates formation of corrugated panels from top, middle, and bottom panel sections;
FIG. 3B illustrates attachment of the corrugated panels to sub-frames;
FIG. 3C illustrates joining of two halves of corrugated panels framed by sub-frames to form the shear panel;
FIG. 3D illustrates installation of vertical tracks on vertical sections of the shear panel;
FIG. 3E illustrates the shear panel being secured to a foundation by an anchor and a hold-down strap;
FIG. 4A is a top end side elevation view of the shear panel;
FIG. 4B is a bottom end side elevation view of the shear panel;
FIG. 5A is a cross-sectional view of the top portion of the shear panel, illustrating a cross-section of a pair of chords joined together;
FIG. 5B is a cross-sectional view of the bottom portion of the shear panel;
FIG. 5C is a cross-sectional view of the vertical section of the shear panel, illustrating positioning of J-plates used to reinforce the shear panel;
FIG. 5D is a cross-sectional view of the vertical section of the shear panel, illustrating how the shear panel is secured to the anchor;
FIG. 6 illustrates a cross-sectional view of the chord;
FIG. 7A is a side elevation view of another embodiment of the corrugated diaphragm shear panel;
FIG. 7B illustrates a base plate of the shear panel of FIG. 7A;
FIG. 8 is an end elevation view of top portion of the shear panel of FIG. 7A, illustrating manner of attachment of the shear panel to a top track that is part of top portion of a wall;
FIG. 9 is a cross sectional view of a vertical section, illustrating a cross sectional view of a pair of chord members in relation to the corrugated diaphragm;
FIG. 10 is an end elevation view of bottom portion of the shear panel of FIG. 7A, illustrating manner of attachment of the shear panel to a foundation to resist shear forces;
FIG. 11A is an isometric view of a bottom assembly that secures the shear panel to the foundation;
FIG. 11B is a side elevation view of lower bottom portion of the shear panel, illustrating manner of attachment of the shear panel to the foundation to resist uplifting forces;
FIG. 11C is a cross sectional top view of lower bottom portion of the shear panel;
FIG. 11D is an end elevation view of bottom portion of the shear panel, illustrating manner of attachment of the shear panel to the foundation to resist the uplifting forces;
FIG. 12A is an end view of a first hold-down bracket; and
FIG. 12B is a side view of the first hold-down bracket.
FIG. 13A is a front elevation view of embodiments of shear panel and hold-down systems;
FIG. 13B is a side section view generally along a vertical centerline of the systems of FIG. 13A;
FIG. 13C is a side elevation view of the systems of FIG. 13A;
FIG. 13D is front elevation view of one embodiment of a shear panel of the systems of FIG. 13A;
FIG. 14A is a detail of FIG. 13B;
FIG. 14B is a detail of FIG. 13D;
FIG. 15 is a plan view of one embodiment of a shear transfer plate;
FIG. 16 is a front elevation of one embodiment of a shear transfer plate;
FIG. 17 is a detail front elevation of FIG. 13A;
FIG. 18 is a detail plan view at D-D of FIG. 13A;
FIG. 19 is a detail plan view at A-A of FIG. 13A;
FIG. 20 is a detail plan view at B-B of FIG. 13A;
FIG. 21A is a detail front elevation of FIG. 13A;
FIG. 21B is a detail side elevation of FIG. 13A with a hold-down assembly installed with an anchor interconnect;
FIG. 21C is a detail side elevation of FIG. 13A with a hold-down assembly installed without an anchor interconnect;
FIGS. 22A and 22B are detail plan section views at generally at C-C of FIG. 13A;
FIGS. 23A and 23B are detail plan section views at generally at B-B of FIG. 13A;
FIGS. 24A and 24B are detail plan section views at generally at C-C of an alternative embodiment of FIG. 13A;
FIGS. 25A and 25B are detail plan section views at generally at B-B of an alternative embodiment of FIG. 13A;
FIGS. 26A-26D are front, rear, side elevation and a plan view respectively of one embodiment of a hold-down bracket;
FIGS. 27A and 27B are front and side elevation views respectively of one embodiment of a slotted support plate;
FIGS. 28A and 28B are plan and side elevation views respectively of one embodiment of a compression plate;
FIG. 29 is a side view of one embodiment of fastener;
FIG. 30 is a side view of one embodiment of hold-down interconnect fastener;
FIGS. 31A and 31B are plan and side elevation views respectively of one embodiment of a compression fastener;
FIGS. 32A and 32B are plan and side elevation views respectively of one embodiment of a hold-down interconnect coupler;
FIG. 33 is an elevation view of one embodiment of an assembled hold-down assembly;
FIG. 34 is a plan view generally at A-A of FIG. 33;
FIG. 35 is a section plan view generally at B-B of FIG. 33;
FIG. 36 is a plan view of another embodiment of a hold-down bracket;
FIG. 37 is a plan view of yet another embodiment of a hold-down bracket;
FIG. 38 is a plan view of another embodiment of compression plate; and
FIG. 39 is a plan view of another embodiment of hold-down assembly in an assembled state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Reference will now be made to the drawings wherein like numerals refer to like parts throughout. FIGS. 1 through 6 relate to embodiments of the invention that use one design of a chord that forms various structures described below. FIGS. 7 through 12 relate to embodiments of the invention that use another design of the chord. It will be appreciated that the chords of different designs both afford advantages in a substantially similar manner that is described below.
FIG. 1 is a perspective view of two adjoining wall frames 101 joined at a corner. The wall frame 101 comprises a plurality of vertical chords 102 that are secured at the top by a horizontal chord comprising an M-track 104, and at the bottom by a bottom track 106. In this embodiment, the chords 102, 104 are steel; however, a person of ordinary skill in the art will appreciate that they can be made of a number of different materials, including wood, without departing from the spirit of the invention. The wall frame 101 is assembled and secured to a foundation 110 in a manner known in the art. Secured to at least one location of each wall frame 101 is a shear panel 100 of one embodiment of the invention. The shear panel 100 is secured to the M-track 104 and the bottom track 106 in a manner described below. Additionally, the shear panel 100 is secured to the foundation 110 by a hold-down strap 114 and an anchor 112 in a manner described below. It will be appreciated that the shear panel 100, when secured to the wall frame 101 and the foundation 110, provides the wall frame 101 with structural integrity to substantially resist shear forces and uplifting forces applied to the wall frame 101.
FIG. 2A illustrates a side elevation view of the shear panel 100 comprising a corrugated diaphragm 120 framed by vertical chord sections 122, a top horizontal section 124, and a bottom horizontal chord section 126. FIG. 2B illustrates an end elevation view of the shear panel 100, showing that the profile of the shear panel 100 is such that when installed in the wall frame 101, the shear panel 100 fits substantially flush with the wall frame 101 and does not protrude out. FIG. 2C illustrates a plan sectional view of the shear panel 100. A cross-section of the vertical section 122 shows that the vertical section 122 is comprised of shaped chord members joined together. As will be described below in greater detail, the chord members of the vertical sections 122, as well as the top chord section 124 and the bottom chord section 126, increase the structural integrity of the shear panel substantially.
FIGS. 3A to 3E illustrate a sequence of assembly of one embodiment of the shear panel 100. In FIG. 3A, the corrugated diaphragm 120 comprises top panel sections 131 a, 131 b, middle panel sections 132 a, 132 b, and bottom panel sections 133 a, 133 b. The top panel section 131 b is substantially same as the top panel section 131 a, and is oriented such that it forms a mirror image of the top panel section 131 a with respect to a plane that is in between and substantially parallel to the planes defined by the top panel sections 131 a, 131 b. Similarly, the middle panel sections 132 a, 132 b and the bottom panel sections 133 a, 133 b form symmetric structures.
In one embodiment, the top panel section 131 a is attached to the middle panel section 132 a by a butt joint 138 facilitated by a flat gusset strap 134. The gusset strap 134 is clinched to each of the panel sections 131 a, 132 a so as to form the joint 138. Similarly, the bottom panel section 133 a is attached to the middle panel section 132 a via gusset strap 134 so as to form a corrugated panel 130 a. A corrugated panel 136 b is formed in a similar manner.
Each of the two corrugated panels 130 a and 130 b comprises a plurality of corrugations 137 that run generally horizontally. In one embodiment, the sectional profile of the corrugation 137 resembles a square wave pattern. The corrugation 137 comprises a recessed flute 135 and an external flute 136, wherein the recessed flute 135 defines a recess in the corrugated diaphragm 120 when viewed from either side of the corrugated diaphragm 120. The external flute 136 and the recessed flute 135 are interconnected by a interconnecting section 310 a(b). The external flutes 136 and the recessed flutes 135 are parallel to the plane of the corrugated panels 130 a, 130 b, and the interconnecting sections 310 a, 310 b are diagonal to the direction of the external and recessed flutes 136, 135. The interconnecting sections 310 a, 310 b are oriented diagonally such that the vertical distance between the closest edges of the adjacent external flutes 136 is larger than the vertical dimension of the recessed flute 135. The degree of diagonality of the interconnecting sections 310 a, 310 b varies, but the mechanical advantage provided remains substantially similar.
The corrugation comprises the recessed flute 135 attached to the interconnecting section 310 b, which in turn is attached to the external flute 136. The external flute 136 is attached to the interconnecting section 310 a. This structure is repeated so as to form the corrugated panels 130 a, 130 b.
The two corrugated panels 130 a and 130 b are secured together at contact points along the back sides of the recessed flutes 135 in a manner described below to form the corrugated diaphragm 120. It will be understood that the recessed flute 135 and the external flute 136 are also referred to hereinafter as a groove and a ridge, respectively.
FIG. 3B illustrates the corrugated panels 130 a, 130 b being attached to sub-frames 140 a, 140 b. The sub-frame 140 a comprises chords 141 a, 142 a, and 143 a. The sub-frame 140 b forms a substantial mirror image of the sub-frame 140 a. The corrugated panel 130 a is attached to the sub-frame 140 a in a manner described below to form a sub-panel 144 a, and similarly, a sub-panel 144 b comprises the corrugated panel 130 b attached to the sub-frame 140 b.
FIG. 3C illustrates the sub-panels 144 a and 144 b being conjoined together. The two sub-panels 144 a, 144 b are secured to each other in a manner described below. The chords 141 a and 141 b, when secured together, become the top section 124, as illustrated in FIG. 3D. Similarly, the chords 143 a and 143 b become the bottom section 126. As illustrated in FIG. 3D, the chords 142 a and 142 b are secured together, and vertical tracks 123 are attached so as to form the vertical sections 122.
FIG. 3E illustrates the fully assembled shear frame 100 being secured to the foundation 110. In one embodiment, the hold-down strap 114 comprises a U-shaped member with a first section 115 a and a second section 115 b attached by a base section 115 c therebetween so as to define a recess 113. The recess 113 is sized to receive the shear panel 100 such that the vertical sections 122 can be secured to the inside surfaces of the first and second sections 115 a, 115 b in a manner described below. The hold-down strap 114 further comprises openings (not shown) at the base, the openings spaced to match the protrusions of the anchor 112. The base of the hold-down strap 114 is secured to the foundation 110 by an anchor nut 116.
Parts that make up the shear frame 100, as described above in reference to FIGS. 1-3, are now described in greater detail. In particular, various geometries and methods of attachments that contribute to the strength of the shear frame 100 are described. FIGS. 4A and 4B illustrate top and bottom end side elevation views of the shear frame 100, respectively, showing a plurality of attachment points. The corrugated diaphragm 120 is framed by the top section 124 at the top, the vertical sections 122 at the sides, and the bottom section 126 at the bottom. As described above, the corrugated diaphragm 120 comprises two corrugated panels 130 a and 130 b conjoined together. Furthermore, the top section 124, the vertical sections 122, and the bottom section 126 each comprises two chords joined in a substantially symmetrical manner. The attachment points illustrated in FIGS. 4A and 4B only show one side of attachment of the corrugated diaphragm 120 to the sub-frame 140 a(b). It will be understood that the manner of attachments on the other side of the corrugated diaphragm 120 is substantially similar.
The description of attachment hereinafter follows the sequence of assembly of the shear panel 100 described above. In reference to FIG. 3A, FIGS. 4A and 4B illustrate a plurality of clinches 151 at the butt joint 138 that secure the panel sections 131 a(b), 132 a(b), 133 a(b) so as to form the corrugated section 130 a(b). The formed butt joint becomes one of the external flutes 136 of the corrugated diaphragm 120.
In reference to FIG. 3B, wherein the corrugated section 130 a(b) is being attached to the sub-frame 140 a(b), FIGS. 4A and 4B illustrate a plurality of clinches 152 along the top section 124, a plurality of clinches 153 along the vertical sections 122, and a plurality of clinches 154 along the bottom section 126. The vertical dimensions and the corrugation spacing are selected to permit the exterior flutes 136 to coincide with the top and bottom sections 124 and 126 so as to allow the clinches 152 and 154 to secure the corrugated diaphragm 120 to the top and bottom sections 124 and 126. Furthermore, the corrugated diaphragm 120 is sized in horizontal direction such that the clinches 153 are situated at the lateral ends of the exterior flutes 136.
In reference to FIG. 3C, wherein the sub-panels 144 a and 144 b are being assembled together, FIGS. 4A and 4B illustrate a plurality of clinches 150 distributed throughout the recessed flutes 135. When the sub panels 144 a and 144 b are mated, the back sides of the recessed flutes 135 come into contact so as to allow the clinches 150 to be made. The combination of clinching of the corrugated panel 130 a(b) to the sub-frame 140 a(b) and clinching the corrugated panels 130 a and 130 b together contributes to the rigidity of the resulting shear panel 100.
The structural integrity of the wall frame 101 is improved by a manner in which chords are shaped and assembled into sections that form the frame of the shear panel 100, and by a manner in which the shear panel 100 is attached to the wall frame 101 and the anchor 112. FIG. 5A illustrates an enlarged cross-sectional view of the top portion of the shear panel 100. The top section 124 comprises the chords 141 a and 141 b, described in greater detail below, arranged in a substantially symmetric manner. Each of the two chords 141 a, 141 b is secured to the external flute 136 by the top clinches 152 as described above. In one embodiment, the top section 124 is secured to the M-track 104 that defines the top of the wall frame 101, by a plurality of field installed shear transfer screws 156. A plurality of such attachments are performed along the M-track 104 that coincides with the top section 124.
As illustrated in FIG. 5A, the M-track 104 is an elongated member that extends along the top portion of the wall, and has a cross section that comprises a first section 301 and a second section 302 with an interconnecting section 303 interposed therebetween. The first and second sections 301, 302 extend vertically, and the ends of the interconnecting section 303 are attached to the top of the first and second sections 301, 302. The interconnecting section 303 comprises a plurality of folds such that the section 303 includes additional vertical sections 305 interposed between horizontal sections 304. The M-track 104, illustrated in FIG. 5A, further comprises an inverted U-shaped fold 307 near the middle of the interconnecting section 303, such that the M-track 104 contains a total of 6 vertical extensions and 5 horizontal extension in its cross section. The plurality of folds that form the plurality of vertical and horizontal extensions provide greater strength to resist forces directed along vertical and horizontal directions.
The horizontal sections 304 on either sides of the U-shaped fold 307 are secured to the chords 141 a, 141 b by the screws 156. Furthermore, the first and second sections 301, 302 are secured to another portion of the chords 141 a, 141 b by the screws 156.
FIG. 5B illustrates an enlarged cross-sectional view of the bottom portion of the shear panel 100. The bottom section 126 comprises the chords 143 a and 143 b arranged in a substantially symmetric manner. Each of the two chords 143 a, 143 b is secured to the external flute 136 by the clinches 152 as described above. As shown in FIG. 4B, the shear panel 100 is secured to the hold-down strap 114 by a plurality of hold-down screws 162 and a plurality of bolts or cap screws 160. The hold-down strap 114 is in turn secured to the anchor 112 by a plurality of slotted steel capture plates 117 and the anchor nuts 116. As shown in FIG. 5B; the shear frame 100 and hold-down strap 114 assembly is positioned within the recess 107 defined by the bottom track 106.
The bottom track 106 is a U-shaped member that has a cross section with a first leg 321 and a second leg 322 that is connected to the first leg 321 by a base section 323. The recess defined by the first and second legs 321, 322, and the base section 323 is sized to receive the bottom of the shear panel 100 such that the shear panel 100 is substantially aligned with the wall.
Positioning the assembly at substantially center of the bottom track is facilitated by a slot 118 defined by the slotted capture plate 117. FIG. 5D illustrates the slot 118 that allows the assembly to be shifted with respect to the fixed anchor 112 so as to permit the assembly to be substantially centered within the bottom track 106.
FIGS. 5C and 5D illustrate cross-sectional views of the vertical section 122 at two different heights. The vertical section 122 comprises the chords 142 a and 142 b arranged in a substantially symmetric manner. Each of the two vertical chords 142 a, 142 b is secured to the external flute 136 by the clinches 153 as described above. The vertical section 122 further comprises the vertical track 123.
The vertical track 123 extends vertically along the edges of the shear panel 100, and has a U-shaped cross section comprising a first leg 331 and a second leg 332 interconnected by a base section 333 so as to define a recess that partially encloses the pair of chords 142 a, 142 b within its recess. The chords 142 a, 142 b are secured to the vertical track 123 by a plurality of screws 164 extending through the base section 333. At the lower portion of the shear panel 100, as illustrated in FIG. 5D, additional screws extend through the first and second legs 331, 332 and secure the vertical track 123 to the chords 142 a, 142 b. Additionally, the portion of the vertical section 122 that overlaps with the hold-down strap 114 is secured with a plurality of screws 162 that extend through the hold-down strap 114, the vertical track 123, and the chord 142 a(b).
The lower portion of the vertical section 122 is further reinforce by a pair of J-plates 145 a, 145 b, as illustrated in FIGS. 5B and 5C. Situated in the recessed flute 135 area, the J-plate 145 a(b) is secured to its respective chord 142 a(b) by clinches 153. Additionally, the clinches 153 that join the J-plate 145 a(b) to the chord 142 a(b) extend to secure a hex nut 161 adjacent the J-plate 145 a(b). The hex nut 161 receives a bolt or cap screw 160 that extends through the hold-down strap 114, the vertical track 123, and the chord 142 a(b) so as to further secure the J-plate 145 a(b) for reinforcement.
As described above, the sections that make up the frame of the shear panel 100 each comprise of a pair of chords. In one embodiment of the invention described above, the cross-sectional shape of the chord is available as a Deitrich design. In another embodiment of the invention, as described below, the cross-sectional shape of the chord may comprise a different shape without departing from the spirit of the invention.
FIG. 6 illustrates the cross sectional shape of the Deitrich chord 146 referred to above in relation to the shear panel frame. As shown in FIG. 6, the cross section of the chord 146 comprises a plurality of folds, comprising a first segment 341 extending in a first direction. A second segment extends in a second direction from the first segment 341, wherein the second direction is perpendicular to the first direction. A third segment 343 extends in a third direction from the second segment 342, wherein the third direction is perpendicular to the second direction and opposite the first direction. The length of the third segment 343 is longer than that of the first segment 341. A fourth segment 344 extends in a fourth direction from the third segment 343, wherein the fourth direction is perpendicular to the third direction and opposite the second direction. The fourth segment 344 is shorter than the second segment 342. A fifth segment 345 extends in the third direction from the fourth segment 345. A U-shaped fold 349 is interposed between the fifth segment 345 and a sixth segment 346 that is collinear with the fifth segment 345. The U-shaped fold 349 is positioned such that two ends at the top of the “U” joins the fifth and sixth segments 345, 346. A seventh segment 347 extends in the second direction from the sixth segment 346. An eighth segment 348 extends in the first direction from the seventh segment 347.
The first, second, and third segments 341, 342, 343 define a partially enclosed space 350, and the fourth, fifth, sixth, seventh, and eighth segments 344, 345, 346, 347, and 348 define a partially enclosed space 351. The chord 146 has a total of five segments extending in first and third directions, and three segments extending in second and fourth directions. Additionally, the U-shaped fold 349 is positioned between the fifth and sixth segments 345, 346 that together are longer than any other single segment. The fold 349 permits the fifth and sixth segments 345, 346 to maintain rigidity. It will be appreciated that the plurality of folds as described above permit the chord 146 to resist buckling in two lateral dimensions.
As is known in the art, a flat sheet offers substantial resistance to buckling along the direction parallel to the plane of the sheet, but offers little strength in the direction perpendicular to the plane. If the sheet is folded at a right angle, strength is provided in both lateral directions against buckling. In practice, sheets of metal are folded in a variety of manner to provide strength against buckling. Folded structures also offer an additional advantage over a solid structure of similar size by substantially reducing the weight.
The third and eighth segments 343, 348 are substantially coplanar so as to permit another chord to be joined at locations along those segments to yield a composite structure. Similarly, two chords can be joined at the first segments 341 to form another composite structure such as the various sections of the shear frame 100 described above.
It will be appreciated that the plurality of folds in the chord 146 afford high strength with relatively low weight. Furthermore, the shape of the cross section of the chord 146 permits two or more chords 146 to be joined together, in manners described above, to yield stronger structures. The light weight and high compressive strength make the chord 146 a highly suitable material for construction applications such as frame sections and wall columns, due to structural advantages described above.
Another component that contributes to the overall strength of the shear panel 100 is the corrugated diaphragm 120. In particular, the generally horizontal corrugation comprising alternating recessed and exterior flutes with interconnecting sections contribute to the strength of the shear frame 100. The exterior flutes on both sides of the corrugated diaphragm 120 define an enclosed space, essentially making the geometry of the diaphragm resulting from the conjoining of the two separate diaphragm panels a series of connected horizontal tubular beams. In one embodiment, the cross section of such a beam is hexagonal in shape. Since the corrugations are generally horizontal, the corrugated diaphragm 120 has high compressive and tensile strength along the horizontal direction, which is also the primary directional component of a typical shear force, for which the panel is designed.
A lateral load shear force acting on a building is transmitted to the wall at the top or bottom, and if unmitigated with some form of bracing or strengthening, the rectangular geometry of the wall does not offer sufficient resistance against lateral movement of the top or bottom of the wall. Thus, the rectangular structure may become a parallelogram shaped structure due to the shear force. For example, an earthquake often shakes a building in a lateral motion, and the resulting shear forces act on the bottom of the wall. In another example, a strong wind blowing at the side of the building causes shear forces at the top of the wall. A shear force at the top of the wall not only tends to distort the rectangular shape of the wall, but also tends to apply an uplifting force at certain locations along the bottom of the wall. If the wall is not secured sufficiently to the foundation, the wall may detach from the foundation.
The shear panel 100 described herein mitigates the forces that tend to make the wall's top or bottom move relative to other parts of the building. The shear panel 100 described above is a substantially rigid structure, particularly against horizontal forces parallel to the plane of the shear panel 100. The shear panel 100 is secured to the wall at the top and bottom of the wall in a manner described above, such that the plane of the shear panel 100 is substantially coplanar with the plane of the wall. Thus, shear forces acting on the wall are mitigated and dissipated by the rigid yet ductile shear panel 100 to inhibit the rectangular structure of the wall from being distorted to a parallelogram shape. A shear force acting on the top of the wall gets transferred to the lower part of the building through the shear panel 100, and is thus dissipated. A shear force acting on the bottom of the wall is transmitted to the upper part of the building through the shear panel 100, thus causing the upper part of the wall to move in unison with the lower part. In either case, the shear panel 100 helps maintain the rectangular geometry of the wall, and thus its structural integrity.
The employment of corrugated sheet diaphragms introduces a new variation in the concept of sheet diaphragm assemblies in that the three-dimensional geometry of a corrugated diaphragm provides an inherent degree of ductility to the diaphragm component of a shear-resisting assembly. Consequently the third dimension of the corrugated diaphragm provides a physical structure which can partially collapse or compress under certain conditions of force or strain without being destroyed. The term “destroyed”, as applied to the discussion of corrugated sheet diaphragms, is defined as meaning the condition wherein relatively thin sheet metal which has deformed beyond tensile yield strength limits of the material. It is believed that the tendency to buckle at the compression members of the vertical chords is reduced when a corrugated diaphragm is employed which, by virtue of its internal compression capabilities, provides controlled ductility in the shear panel.
FIGS. 7 through 12 illustrate another embodiment of the invention, wherein a shear panel 200 comprises chord members 222 of unique design, and attachment assemblies adapted to attach the shear panel to top and bottom of the wall. The design of the chord 222 is described below in reference to FIG. 9.
FIG. 7A illustrates the shear panel 200 comprising a corrugated diaphragm 210 is interposed between two vertical sections 220. The shear panel 200 further comprises a top assembly 230 that secures the shear panel 200 to the top portion of the wall in a manner described below, and a bottom assembly 240 that secures the shear panel 200 to a foundation 243 in a manner described below.
The shear panel 200 is secured to the foundation 243 via anchor bolts 241 and 242 that are pre-installed in the foundation 243. It is noted, however, that anchor bolts which are retrofitted into the foundation may also apply to the utilization of the invention herein described. Preferably, the anchor bolts 241 are ⅝″ diameter steel U-bolts. The anchor bolt 241 and its associated attachment parts are adapted to resist horizontal base shear forces acting on the shear panel 200. The hold-down anchor bolts 242 are preferably ¾″ diameter steel u-bolts and their associated attachment parts are adapted to resist uplifting forces acting on the shear panel 200.
FIG. 7B illustrates a base plate 250 that facilitates securing of the shear panel 200 to the foundation 243 through the connection of the horizontal base shear bolts 241. The base plate 250 comprises a flat portion 253 and vertical portions 254 that are illustrated as folded out dashed lines in FIG. 7B. The flat portion 253 defines holes 251 sized to receive the anchor bolt 241. The flat portion 253 further defines holes 252 sized to receive the anchor bolt 242. The holes 252 are adapted to allow limited range of positioning of the anchor bolt 242 so as to allow the shear panel 200 to be positioned properly with respect to the wall and the foundation 243. The vertical portions 254 attach to the corrugated diaphragm 210 in a manner described below. The base plate 250 is preferably formed from a minimum thickness of 14 gauge steel. The base plate 250 is illustrated in relation to the bottom track 246. The bottom track 246 is described in greater detail below.
FIG. 8 illustrates attachment of the shear panel 200 to the top of the wall via the top assembly 230. The top assembly 230 comprises a top track 231 that is attached to the top portion of the wall (not shown), and a hat channel 232 that secures the top track 231 to the corrugated diaphragm 210.
The top track 231 comprises a U-shaped cross section having a first leg 401 and a second leg 402 with a base section 403 interposed therebetween so as to define a recess sized to receive the top portion of the shear panel 200. The hat channel 232 comprises a cross section having a U-shaped portion with a first leg 411 and a second leg 412 with a base section 413 interposed therebetween. The hat channel 232 further comprises a first extension 415 extending from the first leg 411 on the opposite side from the base section 413, and a second extension 416 extending from the second leg 412 on the opposite side from the base section 413. The first and second extensions 415, 416 are substantially coplanar to each other, and both are substantially parallel to the base section 403 of the top track 231 so as to allow attachment using screw and/or clinch 234.
The first and second legs 411, 412 of the hat channel 232 are substantially parallel, and are spaced to fit within a hemmed external flute 238 that forms the uppermost external flute in the shear panel 200. As is illustrated in FIG. 8, the hemmed flute 238 comprises the end section of the corrugated panels 210. Specifically, the hemmed flute 238 comprises folding the metal sheet at the top of the corrugated panels 210 to form a double layer of metal so as to increase the strength of the hemmed flute 238 for attachment to the first and second legs 411, 412 of the hat channel 232 via screws 233. Thus, the hat channel 232 interconnects the corrugated diaphragm 210 to the top track 231.
FIG. 8 also illustrates the cross section of the corrugated diaphragm 210 interposed between two chords 222. The diaphragm 210 comprises a plurality of recessed flutes 236 and external flutes 235 arranged in an alternating manner. The recessed and external flutes 236, 235 are connected by an interconnecting section 420 so as to form the corrugated structure described above. The diaphragm 210 is made by conjoining two corrugated panels together in a substantially symmetric manner, as described above in reference to FIGS. 3A-C, by a plurality of clinches 237.
FIG. 9 illustrates a cross sectional view of the vertical section 220, comprising two chords 222 and a vertical track 221. Also shown is a portion of the hold-down assembly 229 that is described in detail below. The chord 222 has a cross section that comprises a first section 431 extending in a first direction, connected to a second section 432 that extends in a second direction, wherein the second direction is perpendicular to the first direction. A third section 433 is attached to the second section 432 and extends in a third direction, wherein the third direction is perpendicular to the second direction and opposite the first direction. A fourth section 434 is connected to the third section 433 and extends in a fourth direction, wherein the fourth direction is perpendicular to the third direction and opposite the second direction. A fifth section 435 is connected to the fourth section 434 and extends in the third direction. A sixth section 436 is connected to the fifth section 435 and extends in the second direction. A seventh section 437 is connected to the sixth section 436 and extends in the third direction. An eighth section 438 is connected to the seventh section 437 and extends in the fourth direction. A ninth section 439 is connected to the eighth section 438 and extends in the first direction. The first, fifth, and ninth sections 431, 435, 439 are substantially coplanar. The third and seventh sections 433, 437 are substantial coplanar. The second, fourth, sixth, and eighth sections 432, 434, 436, 438 are substantially parallel. In total, the chord 222 has 5 sections that extend in the first or third directions, and 4 sections that extend in the second or fourth directions, so as to provide strength as described above in reference to the chord 146.
The chord 222 further defines first, second, and third at least partially enclosed spaces 281, 282, 283, wherein the second space 282 is interposed between the first and third spaces 281, 283. The opening of the first space 281 faces in the same direction as the opening of the third space 283. The opening of the second space 282 faces the opposite direction as that of first and third spaces 281, 283, such that the adjacent openings face alternating directions. The first space 281 includes a lip 284, and the third space 283 includes a lip 285.
The chord 222 is preferably roll formed from a 16 gauge steel. A plurality of bends in the cross sectional shape of the chord 222 makes the chord 222 highly resistant to lateral buckling when the chord 222 is subjected to a compressive force directed along its longitudinal axis of elongation.
The vertical section 220 comprises two chords 222 arranged such that the openings of the first and third spaces 281, 283 of the two chords 222 face each other. As such, the chords 222 are secured to the corrugated diaphragm 210 by a plurality of clinches 223 at portions of the chords 222 that define the second spaces 282. The portions of the two chords 222 that define the first spaces 281 are secured to the vertical track 221 in a manner described below in reference to FIG. 11B.
FIG. 10 illustrates attachment of the shear panel 200 to the foundation 243 at the anchor bolt 241, the attachment adapted to resist horizontal shear forces. A bottom track 246 is positioned on top of the foundation 243 such that a plurality of holes (not shown) permit the anchor bolts 241, 242 to extend therethrough. The bottom track 246 has a U-shaped cross section having a first leg 461 and a second leg 462 with a base section 463 interposed therebetween. The spacing between the first and second legs 461, 462 is selected to receive the bottom portion of the shear panel 200.
The bottom track 246 is sized to receive the flat portion of the base plate 253 that defines the holes 251 (in FIG. 7B), through which the anchor bolt 241 extends through. The anchor bolt 241 is secured by a nut 244 and a washer 245. The corrugated diaphragm 210 is secured to the vertical portion of the base plate 254 by a plurality of screws 233 that extends through the vertical portion 254 and the hemmed external flute 238. The chords 222 are secured to the base track 246 by a plurality of nails 247.
FIGS. 11A-D illustrate attachment of the shear panel 200 to the foundation 243. FIG. 11A illustrates the bottom assembly 240 isolated from the diaphragm 210 and the vertical sections 220. The bottom assembly 240 comprises a hold-down assembly 500 and an anchor assembly 600. The hold-down assembly 500 is adapted to resist uplift forces, and the anchor assembly 600 is adapted to resist base shear forces that induce relative movement between the bottom of the shear panel and the foundation.
The isometric view of the bottom assembly in FIG. 11A illustrates the major components that are described in greater detail below. First and second hold-down brackets 263, 264 are shown in relation to a hold-down bolt 261 that couples with the anchor bolt 242. A plurality of bolts 265 and washer plates 266 secure the hold-down brackets 263, 264 to the diaphragm 210 (not shown in FIG. 11A).
FIG. 11B illustrates securing of the chord 222 to the foundation 243 via the first and second hold-down brackets 263, 264 and the hold-down bolt 261 coupled to the anchor bolt 242. The anchor bolt 242 is coupled to the hold-down bolt 261 by a coupling nut 260. The hold-down bolt 261 extends through an opening defined between the first and second hold-down brackets 263, 264. The hold-down brackets 263, 264 are secured to the chord 222 by a plurality of bolts 265 and a washer plate 266 in a manner described below. The hold-down bolt 261 secures the chord 222 to the foundation 243 by tightening the hold-down bolt 261 with a washer 267 and a compression plate 262 interposed between the head of the hold-down bolt 261 and portions of the top edges of the hold-down brackets 263, 264.
FIG. 11C illustrates a top cross sectional view of the hold-down assembly. In particular, positioning of the hold-down bolt 261 and the compression plate 262 relative to the first and second hold-down brackets 263, 264 are shown. The opening 268 on the compression plate 262 is sized to allow limited range of position adjustment of the hold-down bolt 261 so as to permit proper positioning of the shear frame 200 with respect to the foundation 243.
FIG. 11C further illustrates the hold-down bolt 261 positioned within the space defined by the first and second hold-down brackets 263, 264. Each of the first and second hold-down brackets 263, 264, is U-shaped when viewed from the top as in FIG. 11C, and are sized such that the second hold-down bracket 264 fits within a portion of a recess defined by the first hold-down bracket 263. When tops of the “U” on the first and second hold-down brackets 263, 264 are substantially aligned to each other, the bottoms of the “U” on the first and second hold-down brackets 263, 264 are spaced apart to form the space through which the hold-down bolt 261 extends through.
The first hold-down bracket 263 is interposed between the two chords 222, and is secured to the two chords 222 by the bolts 265 coupled by a nut coupler 271. The nut coupler 271 extends through holes defined by the corrugated diaphragm 210, the first and second hold-down brackets 263, 264, and the chords 222, and butts against recesses on the washer plates 266. The washer plate 266 is sized to fit within the partially enclosed space 282 (FIG. 9), such that when the two bolts 265 are tightened, the two chords 222 are compressed together.
The first and second hold-down brackets 263, 264, and the diaphragm 210 between the chords 210 are inhibited from being collapsed by the nut coupler 271 acting as a spacer, and also by a formed compression filler 272. The compression filler 272 is preferably made from rubber or plastic.
FIG. 11D illustrates a side elevation view of attachment of the two chords 222 to the hold-down brackets 263, 264, and the diaphragm 210 interposed therebetween. The sectional views of the hold-down brackets 263, 264 show their position in the recessed flute portion of the diaphragm 210. The external flute portion of the diaphragm 210 is thus positioned in a cutout 273 in the hold-down brackets, as illustrated in FIG. 12B.
FIGS. 12A and 12B illustrate end and side views of the first hold-down bracket 263. The cutout 273 is sized to receive the external flute of the diaphragm 210 such that the hold-down bracket 263 can be positioned substantially flush with the chords 222. The second hold-down bracket 264 is shaped similar to the first hold-down bracket illustrated in FIGS. 12A, 12B.
Aside from the structural advantages, the shear panel 200 provides an advantage of being able to be substantially prefabricated. In use, field installation of the shear panel 200 to the wall comprises several simple steps. First, the base plate 250 is secured to the foundation 243 by placing the base plate 250 within the bottom wall track 246 , and securing the anchor bolts 241, 242 in manners described above in reference to FIGS. 9-11. The shear panel is then inserted within the vertical legs 254 of the base plate 250. The hold-down bolts 261 are inserted through the washer plates 267 and 262 and then placed through the vertical enclosed space of the hold-down brackets 263 and 264. The hold-down bolt 261 is then threaded into the top opening of coupling nut 260 which has been threaded and tightly secured to the anchor bolt 242. The hold-down bolt 261 is then tightened down firmly securing the shear panel to the embedded anchor bolts 242. The field installed screws 233 are then installed through the prepunched holes in the vertical legs 254 of the base plate 250 and further into the hemmed bottom flutes 238 of the corrugated diaphragm. The shear panel 200 is then secured to the top wall track by the clinches and/or screws 234 as illustrated in FIG. 8. The vertical track 221 is attached to the vertical chords 222 by a plurality of screws 270, as illustrated in FIG. 11B, to complete the installation process.
FIGS. 13A, 13B, 13C provide front, side section, and side elevation views, respectively, of embodiments of a shear panel and hold-down system 1100. The system 1100 is configured to more efficiently transfer shear forces incident on a building, such as from high wind loading and/or seismic forces, to an underlying building foundation. In this embodiment, the system 1100 comprises a shear panel assembly 1102 which is attached to a hold-down assembly 1104. The hold-down assembly 1104 is interconnected to one or more structures of a building foundation and the shear panel 1102 is interconnected at an upper end thereof to other structure of the building 1200 such that lateral or uplift forces, particularly those applied at upper extents of the building are resisted by the physical strength of the shear panel assembly 1102 and its interconnection via the hold-down assembly 1104 to the building foundation. In certain embodiments, the system 1100 also comprises a shear transfer plate 1106 which is also interconnected to the shear panel assembly 1102, as well as the underlying building foundation so as to provide additional resistance against uplift and lateral shifting of the system 1100 and attached building under shear or seismic forces.
In these embodiments, the system 1100 also comprises a top track 1120 and a bottom track 1122 which provide additional structure for interconnection of the system 100 to the building and underline building foundation, respectively.
In this embodiment, the shear panel assembly 1102 comprises a plurality of corrugated panels 1110 such that the shear panel assembly 1102 comprises a corrugated shear panel assembly. In one embodiment, the corrugated panels 1110 comprise light-gauge sheet steel, which is rolled or stamped into a generally angular corrugated pattern. Thus, in this embodiment, the corrugated panels 1110 define outward flutes 1111 and inward flutes 1113 which are alternating and interconnected by a corresponding plurality of webs 1115. In one particular embodiment, the corrugated panels 1110 are formed such that the outward flutes 1111 and inward flutes 1113 join adjacent webs 1115 at an angle α. The angle α can be selected for improved ease of manufacture and/or for improved mechanical properties of the system 1100. In certain embodiments, an angle α of approximately 120° provides a preferred combination of fabrication ease and mechanical properties.
In this embodiment, two corrugated panels 1110 are arranged with each other such that the inward flutes 1113 abut and are substantially aligned with each other vertically, as well as laterally. The abutting corrugated panels 1110 are then joined to each other indicated by the attachment 1124. In various embodiments, the attachment 1124 can comprise clinching, welding, adhesives, threaded fasteners, rivets, or other methods or materials for joining materials. In one preferred embodiment, clinching is at least partially employed as the attachment 1124 as clinching provides a relatively rapid and cost-effective manner of joining materials, particularly those embodiments in which the corrugated panels 1110 comprise light-gauge stamped or rolled steel.
The interconnected corrugated panels 1110 also define a plurality of elongate box structures 1114. In this embodiment, the elongate box structures 1114 are generally contoured as hexagonal prisms defined by a pair of outward flutes 1111 and the adjoining webs 1115 on either side of the two interconnected corrugated panels 11110. As the outlying inward flutes 1113 of the two opposed and interconnected corrugated panels 1110 are joined by the attachment 1124, and are materially continuous with the webs 1115 and outward flutes 1111, the elongate box structure 1114 defines a structurally strong member. The elongate box structure 1114 is resistant to both compressive and tensile loads, as well as torsional loads. Thus any shear forces, indicated in FIG. 13A by the opposed arrows 1101, particularly those acting generally in the plane of the shear panel assembly 102 are strongly resisted by the elongate box structures 1114. In this particular embodiment, the elongate box structures 114 are arranged in a generally horizontal orientation. Shear forces 1101, particularly those acting generally in the plane of the shear panel assembly 1102, would tend to buckle, bend, twist, and/or parallelogram convention panels. However, as the shear panel assembly 1102 of these embodiments defines a three-dimensional structurally strong member defined by a plurality of strong interconnected elongate box structures 1114, the interconnect corrugated panels 1110 of the shear panel assembly 1102 are by themselves strongly resistant to any twisting or parallelogramming. This aspect of the shear panel assembly 1102 is improved by the generally horizontal arrangement of the elongate box structures 1114 as shear forces 1101 acting generally in the plane of the shear panel assembly 1102 would otherwise tend to distort a panel along the horizontal direction.
FIGS. 15 and 16 illustrate in plan and front elevational view respectively, one embodiment of a shear transfer plate 1106. The shear transfer plate is configured for attachment both to other components of the shear panel assembly 1102 as well as to an underlying building foundation. In this embodiment, the shear transfer plate 1106 comprises one or more openings 1126 dimensioned to receive and attach to anchor structures 1130 attached to an underlying building foundation. In this embodiment, the shear transfer plate 1106 also comprises a pair of vertically extending opposed webs 1132 having a plurality of attachment locations 1134 for connection of the shear transfer plate 1106 to other components of the shear panel assembly 1102, such as via a plurality of attachments 1124.
In one embodiment, the system 1100 further comprises one or more anchor fasteners 1136 configured to engage with a respective anchor member 1130 to secure the system 1100 to a building foundation via engagement with the shear transfer plate 1106. As the openings 1126 are preferably dimensioned to closely conform to the dimensions and contours of the anchor members 1130, when attached with respective anchor fasteners 1136 the shear transfer plate 1106 and thereby the shear panel assembly 1102 is restrained against movement with respect to the anchor members 1130 and thereby further with the underlying building foundation. (See FIGS. 17 and 19).
FIGS. 18, 20, and 22A and 22B illustrate additional aspects of certain embodiments of a shear panel and hold-down system 1100. In this embodiment, the system 1100 defines a pair of opposed and generally vertically extending box columns 1116. In one embodiment, the box columns 1116 comprise a first elongate C channel 1142 and a second elongate C channel 1150. In this embodiment, the first C channel 1140 comprises a web portion 1142 attached along opposite edges to flange portions 1144 and which are attached at opposite edge portions to lip portions 1142. Thus, together the lip portions 1146, the flange portion 1144, and the web portion 1142 together define a generally C-shaped rectangular section. In one embodiment, the first and second C channel members 1140, 1150 are row formed from sheet steel. In this embodiment, the second C channel 1150 similarly comprises a web portion 1152 attached along opposite edges to flange portions 1154 which are further attached at opposite edge to lip portions 1156.
In this embodiment, the system 1100 further comprises a third C channel elongate member 1160. The third C channel member 1160 is attached to both the first C channel member 1140 and second C channel member 1150 via a plurality of attachments 1158, such as formed via welding, clinching, fasteners, adhesives, etc. The plurality of attachments 1158 further attach the third elongate C channel member 1160 to both opposed sides of the corrugated panels 1110 of the system 1100. Together the interconnected first, second, and third elongate C channel members 1140, 1150, and 1160 define elongate and generally vertically extending box structures 1162. The box structures 1162 are bounded by the interconnected first, second, and third C channel members to define a continuous and generally rectangular cross-section three-dimensional structure.
It will be understood that the box columns 1116 including in this embodiment the first, second, and third C channel members 1140, 1150, and 1160 as mutually interconnected and as connected to the corrugated panels 110 define a structure extending three dimensionally and internally cross-braced to provide significant resistance to bending or deformation when subject to compression, tensile, and twisting forces. These aspects significantly improve the capacity of the system 1100 to resist shear forces which might otherwise tend to distort or bend the system 1100 and any attached building structure. A further advantage of the system 1100 is that it is dimensioned and configured to readily integrate with existing standard framing dimensions. The system 1100 provides improved strength and durability arising from the combination of contours, materials, and interconnection of the various components of the system 1100 however avoids inconvenient dimensions or protrusions which might require expensive modification of existing designs for incorporation of the system 1100.
FIGS. 24A and 24B illustrate another embodiment of a system 1100 including box columns 116. This embodiment is substantially similar to the previously described embodiment including the box columns 116 and box structure 1162. This embodiment differs however in lacking the second C channel elongate member 1150. Rather, in this embodiment the first C channel member 1140 is attached to a third C channel member 1160 which is attached to corrugated panels 1110, such as via a plurality of attachments 1158. A further difference is that rather than the closed box structure 1162, this embodiment defines an open box structure 1163. The open box structure 1163 comprises multiple independent members interconnected so as to extend three-dimensionally in space. The open box structure 1163 likewise offers significant resistance to bending or deformation under tension, compression, and twisting loads. However, rather than defining an enclosed space as in the closed box structure 1162, this embodiment 1163 maintains an open configuration, e.g., between the opposed lip portions 1146 to provide access to the interior of the open box structure 1163, for example to facilitate manipulation of one or more attachments 1158.
FIGS. 21A-21C, 23A and 23B, 25A and 25B, 26A-26D, 27-35 illustrate embodiments of a hold-down assembly 1104 of the system 1100. The hold-down assembly 1104 is configured to interconnect the shear panel assembly 1102 to an underlying building foundation to restrain lift-off, downward forces, as well as lateral translation to assist securing an attached building to the underlying foundation. In one embodiment, the hold-down assembly 1104 comprises a hold-down bracket 1170 having slots 1172 formed therein (see FIGS. 26A-26D). In this embodiment, the hold-down bracket 1170 describes a generally hat-shaped cross-section and is formed from stamped or rolled sheet steel.
In this embodiment, the hold-down assembly 1104 also comprises slotted plates 1174 also having slots 1176 which are configured to mate with and engage the slots 1172 of the hold-down bracket 1170. The slotted plates 1174 engage in the hold-down brackets 1170 to further box in or interconnect in three dimensions the hold-down bracket 1170 such that the hold-down assembly 1104 has greater structurally resistance to bending and deformation under compression, tension, and twisting forces.
In this embodiment, the hold-down assembly 1104 also comprises a pair of compression plates 1180 dimensioned to be positioned at upper and lower ends of the hold-down bracket 1170. In this embodiment, the hold-down assembly 1104 also comprises an elongate screw 1186 and the compression plates 1180 each define an opening 1182 dimensioned to closely receive the screw 1186. Thus, in this embodiment, the screw 1186 passes through a compression plate 1180 arranged in an upper end of the hold-down bracket 1170 as well as a second compression plate 1180 arranged at a lower end of the hold-down bracket 1170. In this embodiment, the hold-down assembly 1104 further comprises a compression nut 1190 which is manipulated to compress the compression plates 1180 into firm contact with the hold-down bracket 1170 positioned therebetween.
In this embodiment, the hold-down assembly 1104 further comprises a coupler 1192 which is dimensioned to threadably engage with a lower end of the screw 1186 and further configured to threadedly engage with the upper end of a respective anchor member 1130. The screw 1186, the compression 1190, and the coupler 1192 are manipulated to bring the hold-down assembly 1104 into a desired position with respect to the underlying building foundation. In many applications, the location and/or vertical protrusion of the anchor members 1130 are subject to variation. In the desired orientation, the hold-down assembly 1104 is restrained from both upward and downward vertical movement with respect to the corresponding anchor member 1130 and thereby with respect to the underlying building foundation. The coupler 1192 facilitates vertical adjustment of the system 1100. Thus, the system 1100 is adapted to connect at a desired height even with differing protrusion distances of the anchor members 1130 facilitated by the adjustability provided by the coupler 1192 and its engagement with a respective anchor member 1130. The hold-down assembly 1104 is further restrained against lateral translation and bending due to the rigid nature of the materials forming the hold-down assembly 1104.
Thus, the hold-down assembly 1104 as attached to a corresponding anchor member 1170 provides a rigid secure structure for interconnection of an associated shear panel assembly 1102. In this embodiment, the hold-down assembly 1104 comprises a plurality of screws 1184 which are configured for attachment to an associated shear panel assembly 1102. In this embodiment, the screws 1184 are configured for engagement with the sheet metal forming the shear panel assembly 1102, however in other embodiments, the attachment provided by the screws 1184 can be supplemented or replaced by other methods of attachment, for example including welding, clinching, and/or adhesives.
FIG. 36 illustrates a plan view of another embodiment of hold-down bracket 1170. In this embodiment, the hold-down bracket 1170 comprises an outer bracket configured for attachment to and engagement with an inner bracket 1194. In this embodiment, both the outer hold-down bracket 1170 and inner hold-down bracket 1194 describe a generally hat-shaped cross-section with the inner bracket 1170 having a larger height or depth such that the connected inner and outer brackets 1170, 1194 define an internal passage to accommodate the screw 1186.
FIG. 37 illustrates yet another embodiment of hold-down bracket and in this embodiment an inner hold-down bracket 1170 is dimensioned to attach to and engage with an inner hold-down bracket 1194. This embodiment is substantially similar to that embodiment previously described with FIG. 36, however in this embodiment, the inner bracket 1194 defines a trapezoidal hat-shaped section rather than the rectangular hat shaped section of the embodiment illustrated and described with respect to FIG. 36.
FIG. 38 illustrates one embodiment of a slotted compression plate 1194. In this embodiment, the slotted compression plate 1194 comprises an elongate opening 1196 which is generally oval in shape. As can be seen in FIG. 39, the elongate opening 1196 provides lateral clearance for the screw 1186. This aspect facilitates accommodation of lateral mismatch between the system 1100 and one or more anchor members 1130. Thus, the system 1100 provides lateral adjustability to accommodate limited horizontal mispositioning of one or more anchor members 1130 without requiring the expense and time consumption of removal and reinstallation of an anchor member 1130 in an appropriate position. FIG. 39 also illustrates that in this embodiment, the system 1100 comprises a first and a second elongate box members 1198 a and 1198 b. These are attached with a first C channel member 1140 and a third C channel member 1160 together define box structure 1162 of the box column 1116.
Thus, various embodiments provide a shear panel and hold-down system 1100 which is significantly resistant to uplift, compression, and lateral movement forces, such as rising from extreme weather conditions or seismic events to inhibit undesired movement of a building structure with respect to an underlying building foundation. The components of the system 1100 can be formed from well understood rolling and stamping formations to facilitate economical use of high strength materials resistant to environmental degradation, including sheet steel. Fabrication of the system 1100 as well as attachment to other building components is provided with well known, durable, and economical methods and materials for joining components, including use of threaded fasteners, clinching, and/or welding. The system 1100 provides for both vertical and lateral adjustability in the attachment of the system 1100 to an underlying building foundation, such as via the anchor members 1130.
Although the various embodiments of the invention have shown, described and pointed out the fundamental novel features of the invention, it will be understood that various omissions, substitutions and changes in the form of the detail of the device illustrated may be made by those skilled in the art without departing from the spirit of the invention. Consequently, the scope of the invention should not be limited to the foregoing description, but should be defined by the appending claims.

Claims

1. A system for inhibiting unwanted movement between a building and an underlying foundation, the system comprising:

at least one shear panel assembly including corrugated portions and configured to resist bending and twisting distortion and

at least one hold-down assembly configured to attach to the at least one shear panel assembly and to attach to at least one anchor member rigidly engaged with an underlying building foundation so as to resist uplift, downward movement, and lateral movement of the at least one attached shear panel assembly, the at least one hold-down assembly configured to provide a range of vertical attachment adjustment to accommodate a range of extended length of the at least one anchor member.

2. The system of claim 1, wherein the at least one shear panel assembly is further configured for attachment to other building structure to provide resistance to bending and twisting distortion of attached other building structure.

3. The system of claim 1, wherein the at least one shear panel assembly comprises at least one corrugated panel defining opposed flutes.

4. The system of claim 3, wherein the at least one shear panel assembly comprises two connected corrugated panels, each corrugated panel defining inner and outer flutes with webs interposed between the inner and outer flutes.

5. The system of claim 4, wherein the inner and outer flutes connect with the webs at an angle selected to increase at least one of ease of fabrication of the corrugated panels and the structural properties of the at least one shear panel assembly.

6. The system of claim 5, wherein the angle is selected to be approximately 120°.

7. The system of claim 3, wherein the at least one shear panel assembly comprises two connected corrugated panels which together define a plurality of elongate box structures.

8. The system of claim 7, wherein the elongate box structures are configured to extend in a generally horizontal direction in an installed condition of the system.

9. The system of claim 7, wherein the elongate box structures define a generally hexagonal cross-section.

10. The system of claim 1, wherein the hold-down assembly is further configured to provide a range of horizontal adjustability.

11. The system of claim 10, wherein the hold-down assembly comprises a compression plate having an elongate opening dimensioned to receive the anchor member over the range of horizontal adjustability.

12. The system of claim 11, wherein the hold-down assembly comprises a screw and a coupler dimensioned to engage with the screw and with the anchor member such that the coupler can be manipulated to provide the vertical adjustment of the system.

13. The system of claim 12, wherein the hold-down assembly comprises a hold-down bracket configured such that the screw extends through the hold-down bracket and wherein the hold-down assembly defines a three-dimensionally extending box structure for increased resistance to bending and torsional distortion.

14. The system of claim 13, wherein the hold-down bracket comprises slots and the hold-down assembly further comprising slotted plates dimensioned to engage with the slots of the hold-down bracket to thereby in combination define the three-dimensionally extending box structure.

15. The system of claim 13, wherein the hold-down bracket comprises an inner bracket and an outer bracket.

16. The system of claim 13, further comprising compression plates dimensioned to engage at an upper end and a lower end of the hold-down bracket and to engage with the screw such that upwards and downwards forces imparted to the system are transferred to the respective anchor member.

17. The system of claim 1, wherein the system is at least partially formed of steel components and wherein the system is adapted to engage with steel framed buildings.