Steel Design Standards

[Young Vadlapatla]

Allof AISC's current standards are available as free downloads to the public in PDF format. For those interested in printed copies, a limited number of softcover versions of AISC's standards are available for purchase. Visit the home page for each of our standards via the menu to the left to download, buy, or learn more about AISC standards.

The AISC Seismic Provisions apply to the design, fabrication, and erection of structural steel and composite steel and concrete seismic force-resisting systems. They are used in conjunction with the AISC Specification for Structural Steel Buildings. Both LRFD and ASD methods of design are incorporated. Dual-units format provides for both U.S. customary and S.I. units.

The prequalified connections standard has been developed by the AISC Connection Prequalification Review Panel in accordance with Chapter K of the Seismic Provisions for Structural Steel Buildings. These connections have been prequalified for use in special and intermediate steel moment frames without the need for additional testing. Dual-units format provides for both U.S. customary and S.I. units.

Seismic Provisions for Evaluation and Retrofit was developed and approved by the AISC Committee on Specifications. It is a revision to the structural steel provisions provided in the 2017 edition of ASCE/SEI 41, Seismic Evaluation and Retrofit of Existing Buildings, and is intended to be adopted in Chapter 9 of the next edition of that standard. The 2022 version of ANSI/AISC 342 is the first edition of this standard. Dual-units format provides for both U.S. customary and S.I. units.

The AISC Specification provides the generally applicable requirements for the design and construction of structural steel buildings and other structures. The 2022 edition of the AISC Specification and Commentary supersedes and is an update of the 2016 edition. Both LRFD and ASD methods of design are incorporated. Dual-units format provides for both U.S. customary and S.I. units.

The AISC Code of Standard Practice provides a framework for a common understanding of the acceptable standards when contracting for structural steel. As such, it is useful for everyone associated with construction in structural steel. Unless specific provisions to the contrary are contained in the contract documents, the existing trade practices that are contained therein are considered to be the standard custom and usage of the industry and are thereby incorporated into a contract between the related parties.

This Standard applies to the design of structural members cold-formed to shape from carbon or low-alloy steel sheet, strip, plate, or bar not more than 1 in. (25.4 mm) in thickness and used for load-carrying purposes in buildings, and structures other than buildings provided allowances are made for dynamic effects.

This Standard applies to the construction of detached one- and two-family dwellings, townhouses, other attached single-family dwellings, and accessory structures not more than three stories in height using repetitive in-line framing practices.

This Standard applies to the overall thermal transmittance (U-factor) of building envelopes containing cold-formed steel framing. This Standard is used to determine thermal transmittance (U-factors) for assessing the energy code compliance of building envelopes for floor assemblies, above-grade wall assemblies, and roof/ceiling assemblies.

AISI does not continue to print and sell pre-2015 editions of AISI Standards. These documents are available free of charge in PDF format from the Wei-Wen Yu Cold-Formed Steel Library at the Missouri University for Science and Technology.

STAINLESS STEELS: AISI is no longer involved with the development and/or maintenance of material standards of stainless steels. Please contact the Specialty Steel Industry of North America (SSINA) for more information on these products.

The American Iron and Steel Institute (AISI) has updated six cold-formed steel (CFS) design standards. AISI is an accredited consensus organization by the American National Standards Institute for developing American National Standards.

AISI serves as the voice of the American steel industry in the public policy arena and advances the case for steel in the marketplace as the preferred material of choice. AISI also plays a lead role in the development and application of new steels and steelmaking technology.

The Eurocodes are a set of structural design standards, developed by CEN (European Committee for Standardisation), to cover the design of all types of structures in steel, concrete, timber, masonry and aluminium. In the UK, they are published by BSI under the designations BS EN 1990 to BS EN 1999; each of these ten Eurocodes is published in several Parts and each Part is accompanied by a National Annex that implements the CEN document and adds certain UK-specific provisions.

This article introduces the Eurocode system, sets out the format that is used and explains the relationship between the Eurocodes, their National Annexes and non-contradictory complementary information (NCCI). It explains that the basis of structural design is set out in BS EN 1990[2] and that this defines the common principles and specifies how design values are to be determined and verified. A brief summary of the various actions (loading) that are defined in EN 1991 is given.

The article introduces the parts of EN 1993 (Eurocode 3) that are required when designing a steel framed building and briefly introduces EN 1994 (Eurocode 4), for composite steel and concrete structures, and EN 1992 (Eurocode 2), which covers the design of the concrete elements in composite structures.

The Governments of the UK and its devolved regions publish documents which provide guidance on the means by which compliance with the Building Regulations in force in that region can be achieved. For structure safety these are: Approved Document A[3] (England); Approved Document A[4] (Wales); Scottish Technical Handbook [5] and Technical Booklet D[6] in Northern Ireland. It should be noted that the English and Welsh Approved Documents have been separate only since 2013. Differences between them are small but one should be aware that they exist. When this article, or any other article on this site, refers to Approved Document A, by default it will be the English version[3].

Approved Document A[3] to the Building Regulations (England) currently references the Eurocodes. It states that: British Standards for structural design based on the Eurocodes were.....implemented by the British Standards Institution on 1st April 2010 and it is these standards with their corresponding UK National Annexes which are now referenced in this Approved Document as practical guidance on meeting Part A requirements.

It further states that: There may be alternative ways of achieving compliance with the requirements and there may be cases where it can be demonstrated that the use of withdrawn standards no longer maintained by the British Standards Institution continues to meet Part A requirements.

It is important to recognise that the regulatory system in the UK is such that the Building Regulations themselves merely make high level demands, for example that a structure is safe. Use of the standards cited in Approved Document A[3] is only one way to demonstrate that requirement has been met.

Each Eurocode comprises a number of 'Parts', which are published as separate documents. Each Part consists of a main body of text, normative annexes, and informative annexes (the 'relevance' of which is decided on a national basis).

The full text of each Eurocode Part is issued initially by CEN (European Committee for Standardisation) in three languages with the above 'EN' designations; national standards bodies may translate the text into other languages but may not make any technical changes. The information given in this text is thus the same for each country in Europe.

The Eurocode text is then provided with a front cover and foreword by each national standards body and published within that country using a designation with the national prefix - for example EN 1990 is published by BSI as BS EN 1990[2]. The text may be followed by a National Annex or a National Annex may be published separately.

The Eurocode Parts contain two distinct types of statement - 'Principles' and 'Application Rules'. The former must be followed, to achieve compliance; the latter are rules that will achieve compliance with the Principles but it is permissible to use alternative design rules, provided that they accord with the Principles (see BS EN 1990[2] 1.4(5)).

The general principle that was adopted in drafting the Eurocodes was that there would be no duplication of Principles or Application Rules. Thus the design basis in BS EN 1990[2] applies irrespective of the construction material or the type of structure.

The guidance given in a National Annex applies to structures that are to be constructed within that country. National Annexes are likely to differ between countries within Europe. The National Annexes for the country where the structure is to be constructed should always be consulted in the design of a structure.

3a8082e126