Abstract:
This paper presents a comprehensive structural analysis of a 44-BWR waste package subjected to a vertical drop event to evaluate its integrity under potential accident conditions. Using the LS-DYNA V950 finite element code and a detailed finite element representation developed in TrueGrid, the study incorporates material properties, geometric dimensions, and loading conditions to simulate transient dynamic behavior and stress responses. The work includes assumptions regarding elevated temperature material properties, simplifications of internal components, and conservative modeling of impact surfaces to ensure bounding results. The analysis calculates true stress and strain, tangent moduli, and ductility measures to accurately model plastic deformation during impact. Results highlight maximum stress intensities in the outer and inner shells under various temperatures, validating the adequacy of the mesh and the conservative nature of the approach. By focusing on stress distributions, allowable stress limits, and the influence of elevated temperatures, the study demonstrates how finite element analysis serves as a crucial tool in predicting waste package performance during drops and verifying compliance with quality assurance requirements. This analysis provides a technical foundation for safety assessments of waste containment systems under realistic and bounding impact scenarios.
