Progressive collapse vulnerability of industrial steel pallet racks: a numerical investigation

The potential for disproportionate progressive collapse in steel pallet racking systems represents a critical, yet under-coded, safety concern in industrial logistics. Current design standards provide a comprehensive framework for structural design; however, explicit and systematic provisions for the assessment of progressive collapse and robustness under accidental scenarios remain limited. This paper presents a preliminary numerical investigation into the progressive collapse behaviour of commercially available rack configurations. A dynamic column loss methodology is adopted to simulate accidental damage scenarios, and the structural response and residual capacity are analysed following both perimeter and interior column removals. The results highlight a marked susceptibility to collapse propagation, indicating that system robustness is not inherently ensured by conventional design practices. Although limited in scope, this initial assessment provides quantitative evidence of the vulnerability of typical rack systems and supports the need for the integration of robustness principles into future design frameworks. These preliminary findings are intended to inform ongoing experimental and numerical research and to contribute to the development of enhanced, performance-based guidelines for the next generation of rack design codes.