Failure Behaviour and Acceptance Criteria of Steel materials for Free-Drop Analysis of Waste Containers

Abstract

Steel waste containers shall be designed to maintain their structural integrity in all applicable loads. Maintaining such integrity during conceivable free-drop accidents is a design matter of great concern during on-site or in-facility lifting. The possible drop cases, such as crane failure during lifting operation, are important to public safety. A drop case can cause damage to the structural components, affect the shipping activities, and might further cause leakage of radioactive material in the worst scenario. To evaluate the possible damage to a waste container for design purposes, a sophisticated numerical analysis is commonly performed to account for geometrical and material nonlinearities, as well as structural stiffness degradation and strength deterioration during the free-drop impact condition. The purpose of this paper is to perform a verification study for a flat steel specimen with 316L material using LS-DYNA material models *MAT24. The true stress-strain relationship for 316L stainless steel is assigned to the *MAT24 model and the output in terms of engineering stress-strain relationship is calculated and compared with the experimental result up to the onset of necking. The necking and up to fracture response behaviour are assessed. A discussion of ASME strain-based acceptance criteria with strain limits is performed, and the ASME strain-based design check is illustrated.