SCANS (Shipping Cask ANalysis System): A Microcomputer Based Analysis System for Shipping Cask Design Review. Volume 3. Theory Manual, Lead Slump in Impact Analysis and Verification of Impact Analysis.

摘要

A computer system called SCANS (Shipping Cask ANalysis System) has been developed for the staff of the U.S. Nuclear Regulatory Commission to perform confirmatory licensing review analyses. The SCANS can handle problems associated with impact, heat transfer, thermal stress, and pressure. A new methodology is developed for SCANS to analyze the lead slump behavior of lead-shielded casks during a postulated impact with an unyielding surface. The methodology is an expansion of the existing lumped-parameter impact analysis method. It is assumed that the lead and the steel cylinders are not bonded as opposed to the existing bonded-lead assumption. The lead and the steel cylinders are treated as an elastic medium and thin elastic shells, respectively. The shielding reduction, or the permanent lead slump at the opposite end of impact, is obtained by converting the elastic strain energy of the lead into plastic deformation. The interface pressure between the lead and the steel, the hoop stress in the steel shells, and the reduction in shielding are among items that can be calculated. The adequacy of this lead slump methodology is established by comparing results with those obtained from rigorous finite element analyses and from cask impact tests.