Tech Note 559: Design Considerations for Flexural and Lateral-Torsional Bracing
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Summary: Load bearing cold-formed/light gauge steel (CFS/LGS) framed walls are typically designed for a combination of axial and lateral out-of-plane (flexural) loading. Under this loading condition, common C-section studs may be susceptible to local, torsional, flexural, torsional-flexural, lateral-torsional or distortional buckling. The response performance of the stud depends on a number of parameters most notably how it is supported along its length (including its ends), the relative magnitudes of the applied loads and the distribution of these loads. This Technical Note discusses the behavior of the typical wall stud and provides some practical considerations for design of torsional-flexural and lateral-torsional bracing. Recommendations and considerations suggested in this technical note are done in accordance with acceptable practices and existing design documents.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
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Tech Note 562-22: Powder-Actuated Fasteners in Cold-Formed Steel Construction
This Technical Note updates and replaces Tech Note 562
Summary: Power-actuated fasteners (PAF’s) are industry standard for attachment of cold-formed steel (CFS) steel framing members, usually track, to concrete, CMU or steel structural elements. “Power-actuated” is the broad category used to refer to fasteners which are driven directly through the CFS and into the substrate, using a powder, gas, compressed air or electro-mechanically driven tool. Efficient installation of framing systems is greatly enhanced by the use of PAF’s. For CFS-to-steel applications, the specification AISI S100 addresses all relevant limit states with equations and safety/ resistance factors. For CFS-to-concrete, limited guidance is provided but not all limit states are covered. This technical note will provide design guidance based on AISI S100, as well as installation and good detailing practice.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note G801-13: ASTM A1003 – No Cause for Rejection
Summary: Building codes and design standards that reference ASTM International (ASTM) A1003 standard for cold-formed steel framing products have the potential to cause confusion and project delays for those who are unfamiliar with the requirements of this new material standard. This Technical Note, first published in 2008, provides a comparison of the requirements of A1003 with the more familiar standards traditionally used for cold-formed steel framing products, and demonstrates that steel ordered or furnished to the old standards should be no cause for rejection. The 2013 revision references a change to the requirements of ASTM A1003 regarding material thickness when ordering or supplying steel sheet.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note B003-20: Introduction to Building Codes
Summary: The International Code Council develops a suite of building codes that are considered nationally to be the model codes for the building industry. Local jurisdictions adopt, and in some cases amend, the codes and they become the law of the jurisdiction for building design and construction. The adopted building codes are intended to provide minimum requirements to provide a safe building environment. Among other requirements, the code dictates the maximum allowable size of a building based on its intended use, materials used in construction, fire resistance rating of structural elements, and the presence of automatic sprinkler systems. The International Building Code establishes all design loads to be applied to the building or structure. The building code also relies on references to other standards and specifications to ensure the provisions reflect the current industry practice. For cold-formed steel framing, the IBC references the American Iron and Steel Institute’s suite of framing standards as the accepted design methods and procedures.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note G200-21: Chase the Loads: Load Path Considerations for Cold-Formed Steel Light-Frame Construction
This Technical Note updates and replaces CFSEI Technical Note G200-15
Summary: Engineering students are admonished to “chase the loads” in their structural analysis and design courses. A “load path” is the direction in which each consecutive load will pass through framing members and the connected members of a framing assembly. The load path sequence begins at the point of load application, both vertical (gravity, wind uplift or seismic vertical) and lateral, on the structure and works all the way down to the footing or foundation system, ultimately transferring the load of the structure to the foundation. This Tech Note provides insight into the load path considerations for cold-formed steel framing.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note 360: Acoustic Insulation and Sound Transmission in Cold-Formed Steel Construction
Summary: Cold-formed steel has been widely used in commercial buildings, especially in non-load bearing (partitions) and curtain wall applications, and is increasingly used as primary structural members, such as beams and columns, or as load-bearing walls or partitions in commercial and residential construction. The acoustic performance of floors and walls is an important consideration for many buildings.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note G101-08: Design Aids and Examples for Distortional Buckling
Summary: The objective of this Tech Note is to provide design examples and design aids specific to cold-formed steel framing systems that address the new distortional buckling limit states added to AISI-S100 in the 2007 edition. In addition, a method is provided for including rotational restraint, provided by sheathing to members, in the design calculations for distortional buckling. This method has been proposed for the next edition of AISI-S210 (floors and roofs) and AISI-S211 (walls studs) standards and partially mitigates the reduced capacity in the distortional buckling limit state.
Note: This document was originally published as G100-08, corrected to G101-08 in April 2011.
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note F140-16: Welding Cold-Formed Steel
Summary: In cold-formed steel construction, welding is a viable connection method. Of the various forms of welding, arc welding is most commonly used to join both cold-formed steel members and hardware components. Prefabrication of roof trusses, panelization of walls, and hardware connections are all ideal applications where welding may be the preferred joining method. This Tech Note provides information on the applicable codes, processes, procedures, design considerations, fabrication and inspection.
This Technical Note updates and replaces CFSEI Technical Note F140-10
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.
Tech Note G102-09: Designing Cold-Formed Steel using the Direct Strength Method
Summary: The Direct Strength Method is an entirely new design method for cold-formed steel. The Direct Strength Method requires no effective width calculations, eliminates tedious iterations to determine section properties, properly includes interaction effects between elements of the cross-section such as the flange and the web, and opens up the potential to create new sections as it is applicable to nearly any shape that can be formed from cold-formed steel, as opposed to just C, Z and hat shapes. The Direct Strength Method was first adopted in 2004 as Appendix 1 to the North American Specification for the Design of Cold-Formed Steel Structural Members, and the most recent version can be found in the recently published AISI-S100-07. This CFSEI Technical Note introduces the Direct Strength Method and details some of the features of a recently published AISI Design Guide for this Method. The intent of this Tech Note and the Guide is to provide engineers with practical guidance in the application of this new design method.
Note: This document was originally published as G100-09, Corrected to G102-09 in April 2011
Disclaimer: Designs cited herein are not intended to preclude the use of other materials, assemblies, structures or designs when these other designs demonstrate equivalent performance for the intended use. CFSEI documents are not intended to exclude the use and implementation of any other design or construction technique.