Framing System for Steel Stud Framing
The present invention is a framing system for resolving vertical and horizontal movements in light gage, cold formed, steel stud framing. It utilizes at least one corner hinge and a plurality of pivoting stud clips (one for each stud) that accommodate for the deflection of a building as it encounters environmental changes. Additional hinges may be placed axially, along the wall and at the top and bottom of the corner for increased flexibility. Two embodiments of stud pivot clips, one utilizing direct attachment and arcuate slots, the other utilizing a pivotable connection plate, are disclosed; as are two hinge embodiments.
This Application claims priority as a continuation of prior filed U.S. application Ser. No. 13/833,564, filed Mar. 15, 2013, which in turn claims priority as a non-provisional perfection of U.S. Provisional Application No. 61/616,350, filed Mar. 27, 2012. Both prior applications are incorporated by reference herein in their entirety.
FIELD OF THE INVENTIONThe present invention relates to the field of building construction and more particularly relates to a structural framing system for accommodating building movements.
BACKGROUND OF THE INVENTIONThe current 2012 International Building Code and most prior model building codes used in the United States (UBC, SBC, BOCA) dating back at least as far as 1972 have required non-structural building enclosures (aka: “facades”, “building skins”, “cladding”) to be designed to accommodate building movements. Said movements include, but are not limited to, vertical displacements of perimeter framing members (spandrel beams) caused by the application of live and other superimposed gravity loads, and the horizontal building movements of the primary structural Lateral Force Resisting System(s) (LFRS) caused by wind, seismic, and other lateral forces. There are many ways to resolve both vertical and lateral movements in light gage, cold formed, steel stud framing (LGCFSSF), in the field of the wall (along a straight run of wall away from building corners) via nested tracks, slotted tracks, slide clips, and several other mechanisms that are currently in the marketplace. These current methods and systems leave accommodation of lateral movements at the corner areas of buildings largely unresolved. Most current framing details and connection systems for LGCFSSF do not specifically address the unique conditions at building corners. Most current LGCFSSFSs require/assume some level of distress and/or failure of the enclosure system at building corners, have extremely large visible joints (to separate the two adjacent walls meeting at the building corner to avoid contact), or include a system that requires the use of a horizontal slotted bent metal angle and special finish materials other than the typical cladding material and at the corner: a special material that can undergo traction and contraction forces. Depending on the magnitude of the lateral forces and the lateral stiffness of the building, said building corners may undergo extreme distress and even member failures due to the bi-directional attitude of building movement at corners; lateral movement in two orthogonal planes intersecting at the corner. Alternatively large joints are needed—joints in the order of 3″ to 6″ in some cases. This current state of the art is the reason for the need for a better resolution of enclosure wall performance at building corners.
The present invention is a framing system that incorporates hinges and pivot capable stud clips in an effort to form corners that are easily assembled without large joints and simultaneously deformable according to the majority of current model codes.
SUMMARY OF THE INVENTIONIn view of the foregoing disadvantages inherent in the known types of framing systems for steel stud framing, this invention provides an improved system which accommodates for deformable corners in the eventual façade of the finished construction. As such, the present invention's general purpose is to provide a new and improved framing system that utilizes vertical, pivoting studs, horizontal header-struts (top and bottom tracks), selectively placed pre-fabricated/pre-manufactured horizontal-plane rotational hinges in the top and bottom track, and pre-fabricated/pre-manufactured vertical-plane rotational stud clips, or “pivot clips.” The pivot clips secure the studs to the edge of floor and allow the studs to rotate freely as driven by story drift displacements. The framing assembly accommodates building movements at building corners through controlled non-planar deformation of the corner region of the building. When properly designed and installed, the framing system disclosed herein significantly mitigates distress at building corners, in some cases, and completely eliminates distress in most cases. The disclosed framing system provides for smaller visible joints in exterior enclosures and allows the use of the typical cladding material without the introduction of other finish materials at the building corner. Critical to the system are the special slab edge vertical plane rotational clips and the horizontal plane hinges in the top and bottom tracks, both of the aforementioned components being ideally pre-fabricated or pre-manufactured and are disclosed herein in two different preferred embodiments each.
The more important features of the invention have thus been outlined in order that the more detailed description that follows may be better understood and in order that the present contribution to the art may better be appreciated. Additional features of the invention will be described hereinafter and will form the subject matter of the claims that follow.
Many objects of this invention will appear from the following description and appended claims, reference being made to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
With reference now to the drawings, the preferred embodiment of the framing system is herein described. It should be noted that the articles “a”, “an”, and “the”, as used in this specification, include plural referents unless the content clearly dictates otherwise. The following reference numbers are used in this specification to identify the following parts of the invention:
10—framing system
12—framing stud
14—upper strut track
16—floor slab
18—lower strut track
20—corner rotational hinge
22—axial rotational hinge
24—lower hinge half
26—hinge pivot pin
28—upper hinge half
30—stud clip
32—clip arcuate slot
34—clip center hole
40—alternate hinge
42—alternate hinge tongue
43—alternate hinge tongue with a bend
44—alternate hinge saddle
46—alternate hinge channel section
48—pivot element
50—alternate stud clip
52—fastening plate
54—plate attachment holes
56—pivot element
58—L-bracket
With reference to
In the region of the system studs are attached to the edge of the floor slab 16 with vertical-plane stud pivot clips 30, the studs extend below the floor to some predetermined elevation (normally the elevation of the head of the window below the floor) and extend up to a similar relative elevation above the floor to which they are attached. Girt-strut track elements 14, 18 run along the top and bottom of the studs, tying the studs 12 together and preventing rotation of the studs 12 about their vertical axis (twisting). A gap is provided between the bottom of the system at one floor and the top of the system at the floor below to allow for vertical deflections of the building framing and other movements. No mechanical tie or link is provided, needed, or allowed between the corner framed system from floor to floor within the area between the horizontal plane hinges 22 and the building corner. A horizontal-plane hinge 20 is placed in the top girt-strut track 14 (and sometimes in the bottom girt-strut track 18) at the intersecting corner of the building—called the “corner hinge”. Other horizontal plane hinges 22 are placed in the top track (and sometimes the bottom track) at the ends of the area that undergoes non-planar deformation away from the corner—called “axial hinges”—at one or both sides of the corner, depending on the building configuration. The far end of the axial hinge 22 connects to the typical framing system which continues along the wall away from the corner framing—preferably a nested track system. Vertical dynamic sealant joints are provided in the exterior finish system at locations aligned with or near a vertical line associated with the corner-hinge 20 and axial-hinges 22.
How it Functions:
As the building moves laterally, perpendicular to the face of the exterior wall, the framing in the field of the wall (framing beyond the corner framing system) will (should) tilt in and out of plane as driven by the lateral movement of the building. The stud pivot clips 30 allow for this stud rotation. The axial hinge 22 at the far end of the corner framing system will link the corner framing system to the field framing. The corner framing system will ride along with the field framing at the axial hinge 22, moving the far end of the top girt-strut track 14 with it. The top girt-strut track 14 will gradually transition to the quasi-static corner position at the corner hinge 20 where the studs 12 remain essentially vertical. At the building corner, the perpendicular wall will keep the building corner in vertical alignment, so the wall element adjacent to the tilting field framing will be driven into a non-planar shape (a hyperbolic-paraboloid shape). There is no connection in the corner framed system from floor to floor so no loads are transmitted from floor to floor within the corner framed system. An offset condition will occur when the building displaces. As the building moves laterally, parallel to the face of the building, the field framing will slip along its axis at the top of the wall in the deflection track. Since there is no connection between floors in the system, the corner will simply displace creating an offset (temporary) until the building rights itself.
For optimum performance of the corner framed system, the length of the sides of the corner framed system are based on the amount of story drift intrinsic to the building and the type of finish materials applied to the stud framing, varying from around 5 feet to upwards of 10 to 12 feet.
The top girt-strut track 14, carries an axial load delivered through the corner hinge 20 from the perpendicular forces on the adjacent wall and delivers it through the axial hinge 22 to the wall beyond the corner framed systems, or delivers it to diagonal bracing within the corner framed system (not shown).
Joint sizing is based on many factors including: the distance from face of stud framing to face of finish material, specified thermal gradients, magnitude of lateral building movement at each floor, sealant movement potential, length of the system side elements, and other factors.
The individual, unique components of the system are shown in
An alternate hinge assembly 40 is depicted in
In an alternate embodiment, shown in
Although the present invention has been described with reference to preferred embodiments, numerous modifications and variations can be made and still the result will come within the scope of the invention. No limitation with respect to the specific embodiments disclosed herein is intended or should be inferred.
The top and bottom girt-strut elements may be comprised of a single light gage cold-formed track profile or may be comprised of an assembly or other combinations of tracks, studs, cold-formed brake shapes, or hot-rolled shapes. The pre-fabricated/pre-manufactured pivot and hinge elements can be made by bending, stamping, forging, forming, casting, welding, and/or other suitable fabrication methods, or combinations thereof. The stud pivot clip may have additional features that enhance durability and strength, such as the illustrated ribs, or any other known or later discovered method or structure in the art, such as structural flanges.
Claims
1. A stud pivot clip for a metal framing system, the stud pivot clip comprising: wherein vertical and horizontal movement of the L-shaped bracket with relation to the backing plate is prohibited and the pivoting element is located along a central longitudinal axis of the backing plate.
- a. a generally L-shaped bracket having a two legs at an approximately 90° angle to each other;
- b. a backing plate pivotably connected to one leg of the stud pivot clip by a pivoting element, said pivoting element passing through the one leg of the stud pivot clip by means of a round, central pivot hole approximately equidistant from opposing edges of the one leg of the stud pivot clip and simultaneously being fixedly positioned on the backing plate while the L-shaped bracket is freely rotatable about the pivoting element when the stud pivot clip is assembled;
2. The stud pivot clip of claim 1, the backing plate being bent in a manner to accommodate the pivoting element and not hinder a range of motion of the pivoting element when the backing plate is attached to the metal framing system.
3. The stud pivot clip of claim 1, the L-shaped bracket being bent to accommodate rotational motion relative to the backing plate.
Type: Application
Filed: Nov 9, 2016
Publication Date: Mar 2, 2017
Inventor: Steven G. Judd (West Valley, UT)
Application Number: 15/347,648