Design of steel storage racks - Elastic and inelastic analysis methods

Abstract

New methods of analysis and design were incorporated in the recent draft revision of the Australian Standard for steel storage racks. The new analysis provisions allow the design to based on elastic methods of analysis or inelastic large displacement analysis methods which account for imperfections and other effects influencing the design capacity. In the latter case, the design may be undertaken entirely by analysis without the need for checking member and connection capacities to a structural standard. The paper presents a comparative study of the design capacities of steel rack frames based on linear analysis (LA), geometric nonlinear analysis (GNA) and geometric and material nonlinear analysis (GMNIA). In the case of linear and geometric nonlinear analyses, the design is carried out to the Australian cold-formed steel structures AS/NZS4600. The study includes braced, unbraced and semi-braced frames, and compact and non-compact cross-sections. The paper shows axial force and bending moment paths for geometric and geometric and material nonlinear analyses, and explains the causes of the differences observed in the design capacities obtained using the different types of analysis. The paper provides evidence to support the use of advanced geometric and material nonlinear analysis (GMNIA) for the direct design of steel rack frames without the need for checking section or member capacities to a structural design standard.