S157-17/S157.1-17

1.1 Applicability This Standard applies to limit state design, fabrication, erection, and inspection of aluminum alloy members and assemblies a) intended to comply with building codes such as the National Building Code of Canada (NBCC); or b) not addressed by another CSA Group standard. When this Standard is referenced by other CSA Group standards (e.g., product standards), the requirements of this Standard apply as so specified in the referencing CSA Group standard. Note: Annex A lists some applications to which other standards apply. 1.2 Other standards The use of other standards for the design, fabrication, erection, and/or inspection of members or parts of aluminum structures is neither warranted nor acceptable except where specifically directed in this Standard. The substitution of other standards or criteria for design, fabrication, erection, and/or inspection is expressly prohibited unless specifically directed in this Standard. 1.3 Rational design Where this Standard does not provide requirements for a specific situation, a rational design is to be used, based on appropriate theories, tests, analyses, or engineering experience. The design formulas provided in this Standard may be supplemented by such a rational design, provided that nominal margins (or factors) of safety are at least equal to those intended in the provisions of this Standard. 1.4 Terminology In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application. 1.5 Units of measure The expressions contained herein are dimensionally uniform, and any consistent system of units may be employed. Where dimensions are identified, SI units are used, typically newtons (N) for force, millimetres (mm) for length, and megapascals (MPa = N/mm2) for stress.